Merge remote-tracking branch 'upstream/master' into promiseAll

change-notes/1.24/analysis-cpp.md

@@ -0,0 +1,20 @@
+# Improvements to C/C++ analysis
+
+The following changes in version 1.24 affect C/C++ analysis in all applications.
+
+## General improvements
+
+## New queries
+
+| **Query**                   | **Tags**  | **Purpose**                                                        |
+|-----------------------------|-----------|--------------------------------------------------------------------|
+
+## Changes to existing queries
+
+| **Query**                  | **Expected impact**    | **Change**                                                       |
+|----------------------------|------------------------|------------------------------------------------------------------|
+| No space for zero terminator (`cpp/no-space-for-terminator`) | Fewer false positive results | This query has been modified to be more conservative when identifying which pointers point to null-terminated strings.  This approach produces fewer, more accurate results. |
+
+## Changes to libraries
+
+* 

change-notes/1.24/analysis-javascript.md

@@ -4,6 +4,7 @@
 
 * Support for the following frameworks and libraries has been improved:
   - [react](https://www.npmjs.com/package/react)
+  - [Handlebars](https://www.npmjs.com/package/handlebars)
 
 ## New queries
 

config/identical-files.json

@@ -143,6 +143,11 @@
     "cpp/ql/src/semmle/code/cpp/ir/implementation/Opcode.qll",
     "csharp/ql/src/semmle/code/csharp/ir/implementation/Opcode.qll"
   ],
+  "IR SSASanity": [
+    "cpp/ql/src/semmle/code/cpp/ir/implementation/unaliased_ssa/internal/SSASanity.qll",
+    "cpp/ql/src/semmle/code/cpp/ir/implementation/aliased_ssa/internal/SSASanity.qll",
+    "csharp/ql/src/semmle/code/csharp/ir/implementation/unaliased_ssa/internal/SSASanity.qll"
+  ],
   "C++ IR InstructionImports": [
     "cpp/ql/src/semmle/code/cpp/ir/implementation/raw/internal/InstructionImports.qll",
     "cpp/ql/src/semmle/code/cpp/ir/implementation/unaliased_ssa/internal/InstructionImports.qll",

cpp/ql/src/Security/CWE/CWE-131/NoSpaceForZeroTerminator.ql

@@ -16,28 +16,28 @@
 
 import cpp
 import semmle.code.cpp.dataflow.DataFlow
-import semmle.code.cpp.models.implementations.Memcpy
+import semmle.code.cpp.models.interfaces.ArrayFunction
 
 class MallocCall extends FunctionCall {
   MallocCall() { this.getTarget().hasGlobalOrStdName("malloc") }
 
-  Expr getAllocatedSize() {
-    if this.getArgument(0) instanceof VariableAccess
-    then
-      exists(LocalScopeVariable v, ControlFlowNode def |
-        definitionUsePair(v, def, this.getArgument(0)) and
-        exprDefinition(v, def, result)
-      )
-    else result = this.getArgument(0)
-  }
+  Expr getAllocatedSize() { result = this.getArgument(0) }
 }
 
 predicate terminationProblem(MallocCall malloc, string msg) {
-  malloc.getAllocatedSize() instanceof StrlenCall and
-  not exists(FunctionCall fc, MemcpyFunction memcpy, int ix |
-    DataFlow::localExprFlow(malloc, fc.getArgument(ix)) and
-    fc.getTarget() = memcpy and
-    memcpy.hasArrayOutput(ix)
+  // malloc(strlen(...))
+  exists(StrlenCall strlen | DataFlow::localExprFlow(strlen, malloc.getAllocatedSize())) and
+  // flows into a null-terminated string function
+  exists(ArrayFunction af, FunctionCall fc, int arg |
+    DataFlow::localExprFlow(malloc, fc.getArgument(arg)) and
+    fc.getTarget() = af and
+    (
+      // null terminated string
+      af.hasArrayWithNullTerminator(arg)
+      or
+      // likely a null terminated string (such as `strcpy`, `strcat`)
+      af.hasArrayWithUnknownSize(arg)
+    )
   ) and
   msg = "This allocation does not include space to null-terminate the string."
 }

cpp/ql/src/semmle/code/cpp/dataflow/internal/DataFlowImpl.qll

@@ -464,7 +464,7 @@ private predicate simpleParameterFlow(
 ) {
   throughFlowNodeCand(node, config) and
   p = node and
-  t = getErasedRepr(node.getType()) and
+  t = getErasedNodeType(node) and
   exists(ReturnNode ret, ReturnKind kind |
     returnNodeGetEnclosingCallable(ret) = p.getEnclosingCallable() and
     kind = ret.getKind() and
@@ -475,21 +475,21 @@ private predicate simpleParameterFlow(
   exists(Node mid |
     simpleParameterFlow(p, mid, t, config) and
     localFlowStep(mid, node, config) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   throughFlowNodeCand(node, unbind(config)) and
   exists(Node mid |
     simpleParameterFlow(p, mid, _, config) and
     additionalLocalFlowStep(mid, node, config) and
-    t = getErasedRepr(node.getType())
+    t = getErasedNodeType(node)
   )
   or
   throughFlowNodeCand(node, unbind(config)) and
   exists(Node mid |
     simpleParameterFlow(p, mid, t, config) and
     localStoreReadStep(mid, node) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   // value flow through a callable
@@ -497,7 +497,7 @@ private predicate simpleParameterFlow(
   exists(Node arg |
     simpleParameterFlow(p, arg, t, config) and
     argumentValueFlowsThrough(arg, node, _) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   // flow through a callable
@@ -989,7 +989,9 @@ private class CastingNode extends Node {
  */
 private predicate flowCandFwd(Node node, boolean fromArg, AccessPathFront apf, Configuration config) {
   flowCandFwd0(node, fromArg, apf, config) and
-  if node instanceof CastingNode then compatibleTypes(node.getType(), apf.getType()) else any()
+  if node instanceof CastingNode
+  then compatibleTypes(getErasedNodeType(node), apf.getType())
+  else any()
 }
 
 /**
@@ -1010,7 +1012,7 @@ private class AccessPathFrontNilNode extends Node {
   }
 
   pragma[noinline]
-  private DataFlowType getErasedReprType() { result = getErasedRepr(this.getType()) }
+  private DataFlowType getErasedReprType() { result = getErasedNodeType(this) }
 
   /** Gets the `nil` path front for this node. */
   AccessPathFrontNil getApf() { result = TFrontNil(this.getErasedReprType()) }
@@ -1337,7 +1339,7 @@ private class AccessPathNilNode extends Node {
   AccessPathNilNode() { flowCand(this.(AccessPathFrontNilNode), _, _, _) }
 
   pragma[noinline]
-  private DataFlowType getErasedReprType() { result = getErasedRepr(this.getType()) }
+  private DataFlowType getErasedReprType() { result = getErasedNodeType(this) }
 
   /** Gets the `nil` path for this node. */
   AccessPathNil getAp() { result = TNil(this.getErasedReprType()) }
@@ -2076,7 +2078,7 @@ private module FlowExploration {
     TPartialPathNodeMk(Node node, CallContext cc, PartialAccessPath ap, Configuration config) {
       config.isSource(node) and
       cc instanceof CallContextAny and
-      ap = TPartialNil(getErasedRepr(node.getType())) and
+      ap = TPartialNil(getErasedNodeType(node)) and
       not fullBarrier(node, config) and
       exists(config.explorationLimit())
       or
@@ -2091,7 +2093,9 @@ private module FlowExploration {
     exists(PartialPathNode mid |
       partialPathStep(mid, node, cc, ap, config) and
       not fullBarrier(node, config) and
-      if node instanceof CastingNode then compatibleTypes(node.getType(), ap.getType()) else any()
+      if node instanceof CastingNode
+      then compatibleTypes(getErasedNodeType(node), ap.getType())
+      else any()
     )
   }
 
@@ -2194,7 +2198,7 @@ private module FlowExploration {
       additionalLocalFlowStep(mid.getNode(), node, config) and
       cc = mid.getCallContext() and
       mid.getAp() instanceof PartialAccessPathNil and
-      ap = TPartialNil(getErasedRepr(node.getType())) and
+      ap = TPartialNil(getErasedNodeType(node)) and
       config = mid.getConfiguration()
     )
     or
@@ -2206,7 +2210,7 @@ private module FlowExploration {
     additionalJumpStep(mid.getNode(), node, config) and
     cc instanceof CallContextAny and
     mid.getAp() instanceof PartialAccessPathNil and
-    ap = TPartialNil(getErasedRepr(node.getType())) and
+    ap = TPartialNil(getErasedNodeType(node)) and
     config = mid.getConfiguration()
     or
     partialPathStoreStep(mid, _, _, node, ap) and

cpp/ql/src/semmle/code/cpp/dataflow/internal/DataFlowImpl2.qll

@@ -464,7 +464,7 @@ private predicate simpleParameterFlow(
 ) {
   throughFlowNodeCand(node, config) and
   p = node and
-  t = getErasedRepr(node.getType()) and
+  t = getErasedNodeType(node) and
   exists(ReturnNode ret, ReturnKind kind |
     returnNodeGetEnclosingCallable(ret) = p.getEnclosingCallable() and
     kind = ret.getKind() and
@@ -475,21 +475,21 @@ private predicate simpleParameterFlow(
   exists(Node mid |
     simpleParameterFlow(p, mid, t, config) and
     localFlowStep(mid, node, config) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   throughFlowNodeCand(node, unbind(config)) and
   exists(Node mid |
     simpleParameterFlow(p, mid, _, config) and
     additionalLocalFlowStep(mid, node, config) and
-    t = getErasedRepr(node.getType())
+    t = getErasedNodeType(node)
   )
   or
   throughFlowNodeCand(node, unbind(config)) and
   exists(Node mid |
     simpleParameterFlow(p, mid, t, config) and
     localStoreReadStep(mid, node) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   // value flow through a callable
@@ -497,7 +497,7 @@ private predicate simpleParameterFlow(
   exists(Node arg |
     simpleParameterFlow(p, arg, t, config) and
     argumentValueFlowsThrough(arg, node, _) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   // flow through a callable
@@ -989,7 +989,9 @@ private class CastingNode extends Node {
  */
 private predicate flowCandFwd(Node node, boolean fromArg, AccessPathFront apf, Configuration config) {
   flowCandFwd0(node, fromArg, apf, config) and
-  if node instanceof CastingNode then compatibleTypes(node.getType(), apf.getType()) else any()
+  if node instanceof CastingNode
+  then compatibleTypes(getErasedNodeType(node), apf.getType())
+  else any()
 }
 
 /**
@@ -1010,7 +1012,7 @@ private class AccessPathFrontNilNode extends Node {
   }
 
   pragma[noinline]
-  private DataFlowType getErasedReprType() { result = getErasedRepr(this.getType()) }
+  private DataFlowType getErasedReprType() { result = getErasedNodeType(this) }
 
   /** Gets the `nil` path front for this node. */
   AccessPathFrontNil getApf() { result = TFrontNil(this.getErasedReprType()) }
@@ -1337,7 +1339,7 @@ private class AccessPathNilNode extends Node {
   AccessPathNilNode() { flowCand(this.(AccessPathFrontNilNode), _, _, _) }
 
   pragma[noinline]
-  private DataFlowType getErasedReprType() { result = getErasedRepr(this.getType()) }
+  private DataFlowType getErasedReprType() { result = getErasedNodeType(this) }
 
   /** Gets the `nil` path for this node. */
   AccessPathNil getAp() { result = TNil(this.getErasedReprType()) }
@@ -2076,7 +2078,7 @@ private module FlowExploration {
     TPartialPathNodeMk(Node node, CallContext cc, PartialAccessPath ap, Configuration config) {
       config.isSource(node) and
       cc instanceof CallContextAny and
-      ap = TPartialNil(getErasedRepr(node.getType())) and
+      ap = TPartialNil(getErasedNodeType(node)) and
       not fullBarrier(node, config) and
       exists(config.explorationLimit())
       or
@@ -2091,7 +2093,9 @@ private module FlowExploration {
     exists(PartialPathNode mid |
       partialPathStep(mid, node, cc, ap, config) and
       not fullBarrier(node, config) and
-      if node instanceof CastingNode then compatibleTypes(node.getType(), ap.getType()) else any()
+      if node instanceof CastingNode
+      then compatibleTypes(getErasedNodeType(node), ap.getType())
+      else any()
     )
   }
 
@@ -2194,7 +2198,7 @@ private module FlowExploration {
       additionalLocalFlowStep(mid.getNode(), node, config) and
       cc = mid.getCallContext() and
       mid.getAp() instanceof PartialAccessPathNil and
-      ap = TPartialNil(getErasedRepr(node.getType())) and
+      ap = TPartialNil(getErasedNodeType(node)) and
       config = mid.getConfiguration()
     )
     or
@@ -2206,7 +2210,7 @@ private module FlowExploration {
     additionalJumpStep(mid.getNode(), node, config) and
     cc instanceof CallContextAny and
     mid.getAp() instanceof PartialAccessPathNil and
-    ap = TPartialNil(getErasedRepr(node.getType())) and
+    ap = TPartialNil(getErasedNodeType(node)) and
     config = mid.getConfiguration()
     or
     partialPathStoreStep(mid, _, _, node, ap) and

cpp/ql/src/semmle/code/cpp/dataflow/internal/DataFlowImpl3.qll

@@ -464,7 +464,7 @@ private predicate simpleParameterFlow(
 ) {
   throughFlowNodeCand(node, config) and
   p = node and
-  t = getErasedRepr(node.getType()) and
+  t = getErasedNodeType(node) and
   exists(ReturnNode ret, ReturnKind kind |
     returnNodeGetEnclosingCallable(ret) = p.getEnclosingCallable() and
     kind = ret.getKind() and
@@ -475,21 +475,21 @@ private predicate simpleParameterFlow(
   exists(Node mid |
     simpleParameterFlow(p, mid, t, config) and
     localFlowStep(mid, node, config) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   throughFlowNodeCand(node, unbind(config)) and
   exists(Node mid |
     simpleParameterFlow(p, mid, _, config) and
     additionalLocalFlowStep(mid, node, config) and
-    t = getErasedRepr(node.getType())
+    t = getErasedNodeType(node)
   )
   or
   throughFlowNodeCand(node, unbind(config)) and
   exists(Node mid |
     simpleParameterFlow(p, mid, t, config) and
     localStoreReadStep(mid, node) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   // value flow through a callable
@@ -497,7 +497,7 @@ private predicate simpleParameterFlow(
   exists(Node arg |
     simpleParameterFlow(p, arg, t, config) and
     argumentValueFlowsThrough(arg, node, _) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   // flow through a callable
@@ -989,7 +989,9 @@ private class CastingNode extends Node {
  */
 private predicate flowCandFwd(Node node, boolean fromArg, AccessPathFront apf, Configuration config) {
   flowCandFwd0(node, fromArg, apf, config) and
-  if node instanceof CastingNode then compatibleTypes(node.getType(), apf.getType()) else any()
+  if node instanceof CastingNode
+  then compatibleTypes(getErasedNodeType(node), apf.getType())
+  else any()
 }
 
 /**
@@ -1010,7 +1012,7 @@ private class AccessPathFrontNilNode extends Node {
   }
 
   pragma[noinline]
-  private DataFlowType getErasedReprType() { result = getErasedRepr(this.getType()) }
+  private DataFlowType getErasedReprType() { result = getErasedNodeType(this) }
 
   /** Gets the `nil` path front for this node. */
   AccessPathFrontNil getApf() { result = TFrontNil(this.getErasedReprType()) }
@@ -1337,7 +1339,7 @@ private class AccessPathNilNode extends Node {
   AccessPathNilNode() { flowCand(this.(AccessPathFrontNilNode), _, _, _) }
 
   pragma[noinline]
-  private DataFlowType getErasedReprType() { result = getErasedRepr(this.getType()) }
+  private DataFlowType getErasedReprType() { result = getErasedNodeType(this) }
 
   /** Gets the `nil` path for this node. */
   AccessPathNil getAp() { result = TNil(this.getErasedReprType()) }
@@ -2076,7 +2078,7 @@ private module FlowExploration {
     TPartialPathNodeMk(Node node, CallContext cc, PartialAccessPath ap, Configuration config) {
       config.isSource(node) and
       cc instanceof CallContextAny and
-      ap = TPartialNil(getErasedRepr(node.getType())) and
+      ap = TPartialNil(getErasedNodeType(node)) and
       not fullBarrier(node, config) and
       exists(config.explorationLimit())
       or
@@ -2091,7 +2093,9 @@ private module FlowExploration {
     exists(PartialPathNode mid |
       partialPathStep(mid, node, cc, ap, config) and
       not fullBarrier(node, config) and
-      if node instanceof CastingNode then compatibleTypes(node.getType(), ap.getType()) else any()
+      if node instanceof CastingNode
+      then compatibleTypes(getErasedNodeType(node), ap.getType())
+      else any()
     )
   }
 
@@ -2194,7 +2198,7 @@ private module FlowExploration {
       additionalLocalFlowStep(mid.getNode(), node, config) and
       cc = mid.getCallContext() and
       mid.getAp() instanceof PartialAccessPathNil and
-      ap = TPartialNil(getErasedRepr(node.getType())) and
+      ap = TPartialNil(getErasedNodeType(node)) and
       config = mid.getConfiguration()
     )
     or
@@ -2206,7 +2210,7 @@ private module FlowExploration {
     additionalJumpStep(mid.getNode(), node, config) and
     cc instanceof CallContextAny and
     mid.getAp() instanceof PartialAccessPathNil and
-    ap = TPartialNil(getErasedRepr(node.getType())) and
+    ap = TPartialNil(getErasedNodeType(node)) and
     config = mid.getConfiguration()
     or
     partialPathStoreStep(mid, _, _, node, ap) and

cpp/ql/src/semmle/code/cpp/dataflow/internal/DataFlowImpl4.qll

@@ -464,7 +464,7 @@ private predicate simpleParameterFlow(
 ) {
   throughFlowNodeCand(node, config) and
   p = node and
-  t = getErasedRepr(node.getType()) and
+  t = getErasedNodeType(node) and
   exists(ReturnNode ret, ReturnKind kind |
     returnNodeGetEnclosingCallable(ret) = p.getEnclosingCallable() and
     kind = ret.getKind() and
@@ -475,21 +475,21 @@ private predicate simpleParameterFlow(
   exists(Node mid |
     simpleParameterFlow(p, mid, t, config) and
     localFlowStep(mid, node, config) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   throughFlowNodeCand(node, unbind(config)) and
   exists(Node mid |
     simpleParameterFlow(p, mid, _, config) and
     additionalLocalFlowStep(mid, node, config) and
-    t = getErasedRepr(node.getType())
+    t = getErasedNodeType(node)
   )
   or
   throughFlowNodeCand(node, unbind(config)) and
   exists(Node mid |
     simpleParameterFlow(p, mid, t, config) and
     localStoreReadStep(mid, node) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   // value flow through a callable
@@ -497,7 +497,7 @@ private predicate simpleParameterFlow(
   exists(Node arg |
     simpleParameterFlow(p, arg, t, config) and
     argumentValueFlowsThrough(arg, node, _) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   // flow through a callable
@@ -989,7 +989,9 @@ private class CastingNode extends Node {
  */
 private predicate flowCandFwd(Node node, boolean fromArg, AccessPathFront apf, Configuration config) {
   flowCandFwd0(node, fromArg, apf, config) and
-  if node instanceof CastingNode then compatibleTypes(node.getType(), apf.getType()) else any()
+  if node instanceof CastingNode
+  then compatibleTypes(getErasedNodeType(node), apf.getType())
+  else any()
 }
 
 /**
@@ -1010,7 +1012,7 @@ private class AccessPathFrontNilNode extends Node {
   }
 
   pragma[noinline]
-  private DataFlowType getErasedReprType() { result = getErasedRepr(this.getType()) }
+  private DataFlowType getErasedReprType() { result = getErasedNodeType(this) }
 
   /** Gets the `nil` path front for this node. */
   AccessPathFrontNil getApf() { result = TFrontNil(this.getErasedReprType()) }
@@ -1337,7 +1339,7 @@ private class AccessPathNilNode extends Node {
   AccessPathNilNode() { flowCand(this.(AccessPathFrontNilNode), _, _, _) }
 
   pragma[noinline]
-  private DataFlowType getErasedReprType() { result = getErasedRepr(this.getType()) }
+  private DataFlowType getErasedReprType() { result = getErasedNodeType(this) }
 
   /** Gets the `nil` path for this node. */
   AccessPathNil getAp() { result = TNil(this.getErasedReprType()) }
@@ -2076,7 +2078,7 @@ private module FlowExploration {
     TPartialPathNodeMk(Node node, CallContext cc, PartialAccessPath ap, Configuration config) {
       config.isSource(node) and
       cc instanceof CallContextAny and
-      ap = TPartialNil(getErasedRepr(node.getType())) and
+      ap = TPartialNil(getErasedNodeType(node)) and
       not fullBarrier(node, config) and
       exists(config.explorationLimit())
       or
@@ -2091,7 +2093,9 @@ private module FlowExploration {
     exists(PartialPathNode mid |
       partialPathStep(mid, node, cc, ap, config) and
       not fullBarrier(node, config) and
-      if node instanceof CastingNode then compatibleTypes(node.getType(), ap.getType()) else any()
+      if node instanceof CastingNode
+      then compatibleTypes(getErasedNodeType(node), ap.getType())
+      else any()
     )
   }
 
@@ -2194,7 +2198,7 @@ private module FlowExploration {
       additionalLocalFlowStep(mid.getNode(), node, config) and
       cc = mid.getCallContext() and
       mid.getAp() instanceof PartialAccessPathNil and
-      ap = TPartialNil(getErasedRepr(node.getType())) and
+      ap = TPartialNil(getErasedNodeType(node)) and
       config = mid.getConfiguration()
     )
     or
@@ -2206,7 +2210,7 @@ private module FlowExploration {
     additionalJumpStep(mid.getNode(), node, config) and
     cc instanceof CallContextAny and
     mid.getAp() instanceof PartialAccessPathNil and
-    ap = TPartialNil(getErasedRepr(node.getType())) and
+    ap = TPartialNil(getErasedNodeType(node)) and
     config = mid.getConfiguration()
     or
     partialPathStoreStep(mid, _, _, node, ap) and

cpp/ql/src/semmle/code/cpp/dataflow/internal/DataFlowImplCommon.qll

@@ -57,14 +57,14 @@ private module ImplCommon {
         exists(Node mid |
           parameterValueFlowCand(p, mid) and
           step(mid, node) and
-          compatibleTypes(p.getType(), node.getType())
+          compatibleTypes(getErasedNodeType(p), getErasedNodeType(node))
         )
         or
         // flow through a callable
         exists(Node arg |
           parameterValueFlowCand(p, arg) and
           argumentValueFlowsThroughCand(arg, node) and
-          compatibleTypes(p.getType(), node.getType())
+          compatibleTypes(getErasedNodeType(p), getErasedNodeType(node))
         )
       }
 
@@ -95,7 +95,7 @@ private module ImplCommon {
           argumentValueFlowsThroughCand0(call, arg, kind)
         |
           out = getAnOutNode(call, kind) and
-          compatibleTypes(arg.getType(), out.getType())
+          compatibleTypes(getErasedNodeType(arg), getErasedNodeType(out))
         )
       }
 
@@ -183,7 +183,7 @@ private module ImplCommon {
         exists(Node mid |
           parameterValueFlow(p, mid, cc) and
           step(mid, node) and
-          compatibleTypes(p.getType(), node.getType()) and
+          compatibleTypes(getErasedNodeType(p), getErasedNodeType(node)) and
           not isUnreachableInCall(node, cc.(CallContextSpecificCall).getCall())
         )
         or
@@ -191,7 +191,7 @@ private module ImplCommon {
         exists(Node arg |
           parameterValueFlow(p, arg, cc) and
           argumentValueFlowsThrough(arg, node, cc) and
-          compatibleTypes(p.getType(), node.getType()) and
+          compatibleTypes(getErasedNodeType(p), getErasedNodeType(node)) and
           not isUnreachableInCall(node, cc.(CallContextSpecificCall).getCall())
         )
       }
@@ -226,7 +226,7 @@ private module ImplCommon {
         |
           out = getAnOutNode(call, kind) and
           not isUnreachableInCall(out, cc.(CallContextSpecificCall).getCall()) and
-          compatibleTypes(arg.getType(), out.getType())
+          compatibleTypes(getErasedNodeType(arg), getErasedNodeType(out))
         )
       }
     }
@@ -260,7 +260,7 @@ private module ImplCommon {
       exists(Node mid |
         parameterValueFlowNoCtx(p, mid) and
         localValueStep(mid, node) and
-        compatibleTypes(p.getType(), node.getType())
+        compatibleTypes(getErasedNodeType(p), getErasedNodeType(node))
       )
     }
 
@@ -296,8 +296,8 @@ private module ImplCommon {
         setterCall(call, i1, i2, f) and
         node1.(ArgumentNode).argumentOf(call, i1) and
         node2.getPreUpdateNode().(ArgumentNode).argumentOf(call, i2) and
-        compatibleTypes(node1.getTypeBound(), f.getType()) and
-        compatibleTypes(node2.getTypeBound(), f.getContainerType())
+        compatibleTypes(getErasedNodeTypeBound(node1), f.getType()) and
+        compatibleTypes(getErasedNodeTypeBound(node2), f.getContainerType())
       )
     }
 
@@ -333,8 +333,8 @@ private module ImplCommon {
       exists(DataFlowCall call, ReturnKind kind |
         storeReturn0(call, kind, node1, f) and
         node2 = getAnOutNode(call, kind) and
-        compatibleTypes(node1.getTypeBound(), f.getType()) and
-        compatibleTypes(node2.getTypeBound(), f.getContainerType())
+        compatibleTypes(getErasedNodeTypeBound(node1), f.getType()) and
+        compatibleTypes(getErasedNodeTypeBound(node2), f.getContainerType())
       )
     }
 
@@ -365,8 +365,8 @@ private module ImplCommon {
       exists(DataFlowCall call, ReturnKind kind |
         read0(call, kind, node1, f) and
         node2 = getAnOutNode(call, kind) and
-        compatibleTypes(node1.getTypeBound(), f.getContainerType()) and
-        compatibleTypes(node2.getTypeBound(), f.getType())
+        compatibleTypes(getErasedNodeTypeBound(node1), f.getContainerType()) and
+        compatibleTypes(getErasedNodeTypeBound(node2), f.getType())
       )
     }
 
@@ -384,7 +384,7 @@ private module ImplCommon {
         store(node1, f, mid1) and
         localValueStep*(mid1, mid2) and
         read(mid2, f, node2) and
-        compatibleTypes(node1.getTypeBound(), node2.getTypeBound())
+        compatibleTypes(getErasedNodeTypeBound(node1), getErasedNodeTypeBound(node2))
       )
     }
 
@@ -405,14 +405,14 @@ private module ImplCommon {
         exists(Node mid |
           parameterValueFlowCand(p, mid) and
           step(mid, node) and
-          compatibleTypes(p.getType(), node.getType())
+          compatibleTypes(getErasedNodeType(p), getErasedNodeType(node))
         )
         or
         // flow through a callable
         exists(Node arg |
           parameterValueFlowCand(p, arg) and
           argumentValueFlowsThroughCand(arg, node) and
-          compatibleTypes(p.getType(), node.getType())
+          compatibleTypes(getErasedNodeType(p), getErasedNodeType(node))
         )
       }
 
@@ -443,7 +443,7 @@ private module ImplCommon {
           argumentValueFlowsThroughCand0(call, arg, kind)
         |
           out = getAnOutNode(call, kind) and
-          compatibleTypes(arg.getType(), out.getType())
+          compatibleTypes(getErasedNodeType(arg), getErasedNodeType(out))
         )
       }
 
@@ -531,7 +531,7 @@ private module ImplCommon {
         exists(Node mid |
           parameterValueFlow(p, mid, cc) and
           step(mid, node) and
-          compatibleTypes(p.getType(), node.getType()) and
+          compatibleTypes(getErasedNodeType(p), getErasedNodeType(node)) and
           not isUnreachableInCall(node, cc.(CallContextSpecificCall).getCall())
         )
         or
@@ -539,7 +539,7 @@ private module ImplCommon {
         exists(Node arg |
           parameterValueFlow(p, arg, cc) and
           argumentValueFlowsThrough(arg, node, cc) and
-          compatibleTypes(p.getType(), node.getType()) and
+          compatibleTypes(getErasedNodeType(p), getErasedNodeType(node)) and
           not isUnreachableInCall(node, cc.(CallContextSpecificCall).getCall())
         )
       }
@@ -574,7 +574,7 @@ private module ImplCommon {
         |
           out = getAnOutNode(call, kind) and
           not isUnreachableInCall(out, cc.(CallContextSpecificCall).getCall()) and
-          compatibleTypes(arg.getType(), out.getType())
+          compatibleTypes(getErasedNodeType(arg), getErasedNodeType(out))
         )
       }
     }
@@ -860,4 +860,10 @@ private module ImplCommon {
     or
     result = viableCallable(call) and cc instanceof CallContextReturn
   }
+
+  pragma[noinline]
+  DataFlowType getErasedNodeType(Node n) { result = getErasedRepr(n.getType()) }
+
+  pragma[noinline]
+  DataFlowType getErasedNodeTypeBound(Node n) { result = getErasedRepr(n.getTypeBound()) }
 }

cpp/ql/src/semmle/code/cpp/dataflow/internal/DataFlowImplLocal.qll

@@ -464,7 +464,7 @@ private predicate simpleParameterFlow(
 ) {
   throughFlowNodeCand(node, config) and
   p = node and
-  t = getErasedRepr(node.getType()) and
+  t = getErasedNodeType(node) and
   exists(ReturnNode ret, ReturnKind kind |
     returnNodeGetEnclosingCallable(ret) = p.getEnclosingCallable() and
     kind = ret.getKind() and
@@ -475,21 +475,21 @@ private predicate simpleParameterFlow(
   exists(Node mid |
     simpleParameterFlow(p, mid, t, config) and
     localFlowStep(mid, node, config) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   throughFlowNodeCand(node, unbind(config)) and
   exists(Node mid |
     simpleParameterFlow(p, mid, _, config) and
     additionalLocalFlowStep(mid, node, config) and
-    t = getErasedRepr(node.getType())
+    t = getErasedNodeType(node)
   )
   or
   throughFlowNodeCand(node, unbind(config)) and
   exists(Node mid |
     simpleParameterFlow(p, mid, t, config) and
     localStoreReadStep(mid, node) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   // value flow through a callable
@@ -497,7 +497,7 @@ private predicate simpleParameterFlow(
   exists(Node arg |
     simpleParameterFlow(p, arg, t, config) and
     argumentValueFlowsThrough(arg, node, _) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   // flow through a callable
@@ -989,7 +989,9 @@ private class CastingNode extends Node {
  */
 private predicate flowCandFwd(Node node, boolean fromArg, AccessPathFront apf, Configuration config) {
   flowCandFwd0(node, fromArg, apf, config) and
-  if node instanceof CastingNode then compatibleTypes(node.getType(), apf.getType()) else any()
+  if node instanceof CastingNode
+  then compatibleTypes(getErasedNodeType(node), apf.getType())
+  else any()
 }
 
 /**
@@ -1010,7 +1012,7 @@ private class AccessPathFrontNilNode extends Node {
   }
 
   pragma[noinline]
-  private DataFlowType getErasedReprType() { result = getErasedRepr(this.getType()) }
+  private DataFlowType getErasedReprType() { result = getErasedNodeType(this) }
 
   /** Gets the `nil` path front for this node. */
   AccessPathFrontNil getApf() { result = TFrontNil(this.getErasedReprType()) }
@@ -1337,7 +1339,7 @@ private class AccessPathNilNode extends Node {
   AccessPathNilNode() { flowCand(this.(AccessPathFrontNilNode), _, _, _) }
 
   pragma[noinline]
-  private DataFlowType getErasedReprType() { result = getErasedRepr(this.getType()) }
+  private DataFlowType getErasedReprType() { result = getErasedNodeType(this) }
 
   /** Gets the `nil` path for this node. */
   AccessPathNil getAp() { result = TNil(this.getErasedReprType()) }
@@ -2076,7 +2078,7 @@ private module FlowExploration {
     TPartialPathNodeMk(Node node, CallContext cc, PartialAccessPath ap, Configuration config) {
       config.isSource(node) and
       cc instanceof CallContextAny and
-      ap = TPartialNil(getErasedRepr(node.getType())) and
+      ap = TPartialNil(getErasedNodeType(node)) and
       not fullBarrier(node, config) and
       exists(config.explorationLimit())
       or
@@ -2091,7 +2093,9 @@ private module FlowExploration {
     exists(PartialPathNode mid |
       partialPathStep(mid, node, cc, ap, config) and
       not fullBarrier(node, config) and
-      if node instanceof CastingNode then compatibleTypes(node.getType(), ap.getType()) else any()
+      if node instanceof CastingNode
+      then compatibleTypes(getErasedNodeType(node), ap.getType())
+      else any()
     )
   }
 
@@ -2194,7 +2198,7 @@ private module FlowExploration {
       additionalLocalFlowStep(mid.getNode(), node, config) and
       cc = mid.getCallContext() and
       mid.getAp() instanceof PartialAccessPathNil and
-      ap = TPartialNil(getErasedRepr(node.getType())) and
+      ap = TPartialNil(getErasedNodeType(node)) and
       config = mid.getConfiguration()
     )
     or
@@ -2206,7 +2210,7 @@ private module FlowExploration {
     additionalJumpStep(mid.getNode(), node, config) and
     cc instanceof CallContextAny and
     mid.getAp() instanceof PartialAccessPathNil and
-    ap = TPartialNil(getErasedRepr(node.getType())) and
+    ap = TPartialNil(getErasedNodeType(node)) and
     config = mid.getConfiguration()
     or
     partialPathStoreStep(mid, _, _, node, ap) and

cpp/ql/src/semmle/code/cpp/ir/dataflow/internal/DataFlowImpl.qll

@@ -464,7 +464,7 @@ private predicate simpleParameterFlow(
 ) {
   throughFlowNodeCand(node, config) and
   p = node and
-  t = getErasedRepr(node.getType()) and
+  t = getErasedNodeType(node) and
   exists(ReturnNode ret, ReturnKind kind |
     returnNodeGetEnclosingCallable(ret) = p.getEnclosingCallable() and
     kind = ret.getKind() and
@@ -475,21 +475,21 @@ private predicate simpleParameterFlow(
   exists(Node mid |
     simpleParameterFlow(p, mid, t, config) and
     localFlowStep(mid, node, config) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   throughFlowNodeCand(node, unbind(config)) and
   exists(Node mid |
     simpleParameterFlow(p, mid, _, config) and
     additionalLocalFlowStep(mid, node, config) and
-    t = getErasedRepr(node.getType())
+    t = getErasedNodeType(node)
   )
   or
   throughFlowNodeCand(node, unbind(config)) and
   exists(Node mid |
     simpleParameterFlow(p, mid, t, config) and
     localStoreReadStep(mid, node) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   // value flow through a callable
@@ -497,7 +497,7 @@ private predicate simpleParameterFlow(
   exists(Node arg |
     simpleParameterFlow(p, arg, t, config) and
     argumentValueFlowsThrough(arg, node, _) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   // flow through a callable
@@ -989,7 +989,9 @@ private class CastingNode extends Node {
  */
 private predicate flowCandFwd(Node node, boolean fromArg, AccessPathFront apf, Configuration config) {
   flowCandFwd0(node, fromArg, apf, config) and
-  if node instanceof CastingNode then compatibleTypes(node.getType(), apf.getType()) else any()
+  if node instanceof CastingNode
+  then compatibleTypes(getErasedNodeType(node), apf.getType())
+  else any()
 }
 
 /**
@@ -1010,7 +1012,7 @@ private class AccessPathFrontNilNode extends Node {
   }
 
   pragma[noinline]
-  private DataFlowType getErasedReprType() { result = getErasedRepr(this.getType()) }
+  private DataFlowType getErasedReprType() { result = getErasedNodeType(this) }
 
   /** Gets the `nil` path front for this node. */
   AccessPathFrontNil getApf() { result = TFrontNil(this.getErasedReprType()) }
@@ -1337,7 +1339,7 @@ private class AccessPathNilNode extends Node {
   AccessPathNilNode() { flowCand(this.(AccessPathFrontNilNode), _, _, _) }
 
   pragma[noinline]
-  private DataFlowType getErasedReprType() { result = getErasedRepr(this.getType()) }
+  private DataFlowType getErasedReprType() { result = getErasedNodeType(this) }
 
   /** Gets the `nil` path for this node. */
   AccessPathNil getAp() { result = TNil(this.getErasedReprType()) }
@@ -2076,7 +2078,7 @@ private module FlowExploration {
     TPartialPathNodeMk(Node node, CallContext cc, PartialAccessPath ap, Configuration config) {
       config.isSource(node) and
       cc instanceof CallContextAny and
-      ap = TPartialNil(getErasedRepr(node.getType())) and
+      ap = TPartialNil(getErasedNodeType(node)) and
       not fullBarrier(node, config) and
       exists(config.explorationLimit())
       or
@@ -2091,7 +2093,9 @@ private module FlowExploration {
     exists(PartialPathNode mid |
       partialPathStep(mid, node, cc, ap, config) and
       not fullBarrier(node, config) and
-      if node instanceof CastingNode then compatibleTypes(node.getType(), ap.getType()) else any()
+      if node instanceof CastingNode
+      then compatibleTypes(getErasedNodeType(node), ap.getType())
+      else any()
     )
   }
 
@@ -2194,7 +2198,7 @@ private module FlowExploration {
       additionalLocalFlowStep(mid.getNode(), node, config) and
       cc = mid.getCallContext() and
       mid.getAp() instanceof PartialAccessPathNil and
-      ap = TPartialNil(getErasedRepr(node.getType())) and
+      ap = TPartialNil(getErasedNodeType(node)) and
       config = mid.getConfiguration()
     )
     or
@@ -2206,7 +2210,7 @@ private module FlowExploration {
     additionalJumpStep(mid.getNode(), node, config) and
     cc instanceof CallContextAny and
     mid.getAp() instanceof PartialAccessPathNil and
-    ap = TPartialNil(getErasedRepr(node.getType())) and
+    ap = TPartialNil(getErasedNodeType(node)) and
     config = mid.getConfiguration()
     or
     partialPathStoreStep(mid, _, _, node, ap) and

cpp/ql/src/semmle/code/cpp/ir/dataflow/internal/DataFlowImpl2.qll

@@ -464,7 +464,7 @@ private predicate simpleParameterFlow(
 ) {
   throughFlowNodeCand(node, config) and
   p = node and
-  t = getErasedRepr(node.getType()) and
+  t = getErasedNodeType(node) and
   exists(ReturnNode ret, ReturnKind kind |
     returnNodeGetEnclosingCallable(ret) = p.getEnclosingCallable() and
     kind = ret.getKind() and
@@ -475,21 +475,21 @@ private predicate simpleParameterFlow(
   exists(Node mid |
     simpleParameterFlow(p, mid, t, config) and
     localFlowStep(mid, node, config) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   throughFlowNodeCand(node, unbind(config)) and
   exists(Node mid |
     simpleParameterFlow(p, mid, _, config) and
     additionalLocalFlowStep(mid, node, config) and
-    t = getErasedRepr(node.getType())
+    t = getErasedNodeType(node)
   )
   or
   throughFlowNodeCand(node, unbind(config)) and
   exists(Node mid |
     simpleParameterFlow(p, mid, t, config) and
     localStoreReadStep(mid, node) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   // value flow through a callable
@@ -497,7 +497,7 @@ private predicate simpleParameterFlow(
   exists(Node arg |
     simpleParameterFlow(p, arg, t, config) and
     argumentValueFlowsThrough(arg, node, _) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   // flow through a callable
@@ -989,7 +989,9 @@ private class CastingNode extends Node {
  */
 private predicate flowCandFwd(Node node, boolean fromArg, AccessPathFront apf, Configuration config) {
   flowCandFwd0(node, fromArg, apf, config) and
-  if node instanceof CastingNode then compatibleTypes(node.getType(), apf.getType()) else any()
+  if node instanceof CastingNode
+  then compatibleTypes(getErasedNodeType(node), apf.getType())
+  else any()
 }
 
 /**
@@ -1010,7 +1012,7 @@ private class AccessPathFrontNilNode extends Node {
   }
 
   pragma[noinline]
-  private DataFlowType getErasedReprType() { result = getErasedRepr(this.getType()) }
+  private DataFlowType getErasedReprType() { result = getErasedNodeType(this) }
 
   /** Gets the `nil` path front for this node. */
   AccessPathFrontNil getApf() { result = TFrontNil(this.getErasedReprType()) }
@@ -1337,7 +1339,7 @@ private class AccessPathNilNode extends Node {
   AccessPathNilNode() { flowCand(this.(AccessPathFrontNilNode), _, _, _) }
 
   pragma[noinline]
-  private DataFlowType getErasedReprType() { result = getErasedRepr(this.getType()) }
+  private DataFlowType getErasedReprType() { result = getErasedNodeType(this) }
 
   /** Gets the `nil` path for this node. */
   AccessPathNil getAp() { result = TNil(this.getErasedReprType()) }
@@ -2076,7 +2078,7 @@ private module FlowExploration {
     TPartialPathNodeMk(Node node, CallContext cc, PartialAccessPath ap, Configuration config) {
       config.isSource(node) and
       cc instanceof CallContextAny and
-      ap = TPartialNil(getErasedRepr(node.getType())) and
+      ap = TPartialNil(getErasedNodeType(node)) and
       not fullBarrier(node, config) and
       exists(config.explorationLimit())
       or
@@ -2091,7 +2093,9 @@ private module FlowExploration {
     exists(PartialPathNode mid |
       partialPathStep(mid, node, cc, ap, config) and
       not fullBarrier(node, config) and
-      if node instanceof CastingNode then compatibleTypes(node.getType(), ap.getType()) else any()
+      if node instanceof CastingNode
+      then compatibleTypes(getErasedNodeType(node), ap.getType())
+      else any()
     )
   }
 
@@ -2194,7 +2198,7 @@ private module FlowExploration {
       additionalLocalFlowStep(mid.getNode(), node, config) and
       cc = mid.getCallContext() and
       mid.getAp() instanceof PartialAccessPathNil and
-      ap = TPartialNil(getErasedRepr(node.getType())) and
+      ap = TPartialNil(getErasedNodeType(node)) and
       config = mid.getConfiguration()
     )
     or
@@ -2206,7 +2210,7 @@ private module FlowExploration {
     additionalJumpStep(mid.getNode(), node, config) and
     cc instanceof CallContextAny and
     mid.getAp() instanceof PartialAccessPathNil and
-    ap = TPartialNil(getErasedRepr(node.getType())) and
+    ap = TPartialNil(getErasedNodeType(node)) and
     config = mid.getConfiguration()
     or
     partialPathStoreStep(mid, _, _, node, ap) and

cpp/ql/src/semmle/code/cpp/ir/dataflow/internal/DataFlowImpl3.qll

@@ -464,7 +464,7 @@ private predicate simpleParameterFlow(
 ) {
   throughFlowNodeCand(node, config) and
   p = node and
-  t = getErasedRepr(node.getType()) and
+  t = getErasedNodeType(node) and
   exists(ReturnNode ret, ReturnKind kind |
     returnNodeGetEnclosingCallable(ret) = p.getEnclosingCallable() and
     kind = ret.getKind() and
@@ -475,21 +475,21 @@ private predicate simpleParameterFlow(
   exists(Node mid |
     simpleParameterFlow(p, mid, t, config) and
     localFlowStep(mid, node, config) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   throughFlowNodeCand(node, unbind(config)) and
   exists(Node mid |
     simpleParameterFlow(p, mid, _, config) and
     additionalLocalFlowStep(mid, node, config) and
-    t = getErasedRepr(node.getType())
+    t = getErasedNodeType(node)
   )
   or
   throughFlowNodeCand(node, unbind(config)) and
   exists(Node mid |
     simpleParameterFlow(p, mid, t, config) and
     localStoreReadStep(mid, node) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   // value flow through a callable
@@ -497,7 +497,7 @@ private predicate simpleParameterFlow(
   exists(Node arg |
     simpleParameterFlow(p, arg, t, config) and
     argumentValueFlowsThrough(arg, node, _) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   // flow through a callable
@@ -989,7 +989,9 @@ private class CastingNode extends Node {
  */
 private predicate flowCandFwd(Node node, boolean fromArg, AccessPathFront apf, Configuration config) {
   flowCandFwd0(node, fromArg, apf, config) and
-  if node instanceof CastingNode then compatibleTypes(node.getType(), apf.getType()) else any()
+  if node instanceof CastingNode
+  then compatibleTypes(getErasedNodeType(node), apf.getType())
+  else any()
 }
 
 /**
@@ -1010,7 +1012,7 @@ private class AccessPathFrontNilNode extends Node {
   }
 
   pragma[noinline]
-  private DataFlowType getErasedReprType() { result = getErasedRepr(this.getType()) }
+  private DataFlowType getErasedReprType() { result = getErasedNodeType(this) }
 
   /** Gets the `nil` path front for this node. */
   AccessPathFrontNil getApf() { result = TFrontNil(this.getErasedReprType()) }
@@ -1337,7 +1339,7 @@ private class AccessPathNilNode extends Node {
   AccessPathNilNode() { flowCand(this.(AccessPathFrontNilNode), _, _, _) }
 
   pragma[noinline]
-  private DataFlowType getErasedReprType() { result = getErasedRepr(this.getType()) }
+  private DataFlowType getErasedReprType() { result = getErasedNodeType(this) }
 
   /** Gets the `nil` path for this node. */
   AccessPathNil getAp() { result = TNil(this.getErasedReprType()) }
@@ -2076,7 +2078,7 @@ private module FlowExploration {
     TPartialPathNodeMk(Node node, CallContext cc, PartialAccessPath ap, Configuration config) {
       config.isSource(node) and
       cc instanceof CallContextAny and
-      ap = TPartialNil(getErasedRepr(node.getType())) and
+      ap = TPartialNil(getErasedNodeType(node)) and
       not fullBarrier(node, config) and
       exists(config.explorationLimit())
       or
@@ -2091,7 +2093,9 @@ private module FlowExploration {
     exists(PartialPathNode mid |
       partialPathStep(mid, node, cc, ap, config) and
       not fullBarrier(node, config) and
-      if node instanceof CastingNode then compatibleTypes(node.getType(), ap.getType()) else any()
+      if node instanceof CastingNode
+      then compatibleTypes(getErasedNodeType(node), ap.getType())
+      else any()
     )
   }
 
@@ -2194,7 +2198,7 @@ private module FlowExploration {
       additionalLocalFlowStep(mid.getNode(), node, config) and
       cc = mid.getCallContext() and
       mid.getAp() instanceof PartialAccessPathNil and
-      ap = TPartialNil(getErasedRepr(node.getType())) and
+      ap = TPartialNil(getErasedNodeType(node)) and
       config = mid.getConfiguration()
     )
     or
@@ -2206,7 +2210,7 @@ private module FlowExploration {
     additionalJumpStep(mid.getNode(), node, config) and
     cc instanceof CallContextAny and
     mid.getAp() instanceof PartialAccessPathNil and
-    ap = TPartialNil(getErasedRepr(node.getType())) and
+    ap = TPartialNil(getErasedNodeType(node)) and
     config = mid.getConfiguration()
     or
     partialPathStoreStep(mid, _, _, node, ap) and

cpp/ql/src/semmle/code/cpp/ir/dataflow/internal/DataFlowImpl4.qll

@@ -464,7 +464,7 @@ private predicate simpleParameterFlow(
 ) {
   throughFlowNodeCand(node, config) and
   p = node and
-  t = getErasedRepr(node.getType()) and
+  t = getErasedNodeType(node) and
   exists(ReturnNode ret, ReturnKind kind |
     returnNodeGetEnclosingCallable(ret) = p.getEnclosingCallable() and
     kind = ret.getKind() and
@@ -475,21 +475,21 @@ private predicate simpleParameterFlow(
   exists(Node mid |
     simpleParameterFlow(p, mid, t, config) and
     localFlowStep(mid, node, config) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   throughFlowNodeCand(node, unbind(config)) and
   exists(Node mid |
     simpleParameterFlow(p, mid, _, config) and
     additionalLocalFlowStep(mid, node, config) and
-    t = getErasedRepr(node.getType())
+    t = getErasedNodeType(node)
   )
   or
   throughFlowNodeCand(node, unbind(config)) and
   exists(Node mid |
     simpleParameterFlow(p, mid, t, config) and
     localStoreReadStep(mid, node) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   // value flow through a callable
@@ -497,7 +497,7 @@ private predicate simpleParameterFlow(
   exists(Node arg |
     simpleParameterFlow(p, arg, t, config) and
     argumentValueFlowsThrough(arg, node, _) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   // flow through a callable
@@ -989,7 +989,9 @@ private class CastingNode extends Node {
  */
 private predicate flowCandFwd(Node node, boolean fromArg, AccessPathFront apf, Configuration config) {
   flowCandFwd0(node, fromArg, apf, config) and
-  if node instanceof CastingNode then compatibleTypes(node.getType(), apf.getType()) else any()
+  if node instanceof CastingNode
+  then compatibleTypes(getErasedNodeType(node), apf.getType())
+  else any()
 }
 
 /**
@@ -1010,7 +1012,7 @@ private class AccessPathFrontNilNode extends Node {
   }
 
   pragma[noinline]
-  private DataFlowType getErasedReprType() { result = getErasedRepr(this.getType()) }
+  private DataFlowType getErasedReprType() { result = getErasedNodeType(this) }
 
   /** Gets the `nil` path front for this node. */
   AccessPathFrontNil getApf() { result = TFrontNil(this.getErasedReprType()) }
@@ -1337,7 +1339,7 @@ private class AccessPathNilNode extends Node {
   AccessPathNilNode() { flowCand(this.(AccessPathFrontNilNode), _, _, _) }
 
   pragma[noinline]
-  private DataFlowType getErasedReprType() { result = getErasedRepr(this.getType()) }
+  private DataFlowType getErasedReprType() { result = getErasedNodeType(this) }
 
   /** Gets the `nil` path for this node. */
   AccessPathNil getAp() { result = TNil(this.getErasedReprType()) }
@@ -2076,7 +2078,7 @@ private module FlowExploration {
     TPartialPathNodeMk(Node node, CallContext cc, PartialAccessPath ap, Configuration config) {
       config.isSource(node) and
       cc instanceof CallContextAny and
-      ap = TPartialNil(getErasedRepr(node.getType())) and
+      ap = TPartialNil(getErasedNodeType(node)) and
       not fullBarrier(node, config) and
       exists(config.explorationLimit())
       or
@@ -2091,7 +2093,9 @@ private module FlowExploration {
     exists(PartialPathNode mid |
       partialPathStep(mid, node, cc, ap, config) and
       not fullBarrier(node, config) and
-      if node instanceof CastingNode then compatibleTypes(node.getType(), ap.getType()) else any()
+      if node instanceof CastingNode
+      then compatibleTypes(getErasedNodeType(node), ap.getType())
+      else any()
     )
   }
 
@@ -2194,7 +2198,7 @@ private module FlowExploration {
       additionalLocalFlowStep(mid.getNode(), node, config) and
       cc = mid.getCallContext() and
       mid.getAp() instanceof PartialAccessPathNil and
-      ap = TPartialNil(getErasedRepr(node.getType())) and
+      ap = TPartialNil(getErasedNodeType(node)) and
       config = mid.getConfiguration()
     )
     or
@@ -2206,7 +2210,7 @@ private module FlowExploration {
     additionalJumpStep(mid.getNode(), node, config) and
     cc instanceof CallContextAny and
     mid.getAp() instanceof PartialAccessPathNil and
-    ap = TPartialNil(getErasedRepr(node.getType())) and
+    ap = TPartialNil(getErasedNodeType(node)) and
     config = mid.getConfiguration()
     or
     partialPathStoreStep(mid, _, _, node, ap) and

cpp/ql/src/semmle/code/cpp/ir/dataflow/internal/DataFlowImplCommon.qll

@@ -57,14 +57,14 @@ private module ImplCommon {
         exists(Node mid |
           parameterValueFlowCand(p, mid) and
           step(mid, node) and
-          compatibleTypes(p.getType(), node.getType())
+          compatibleTypes(getErasedNodeType(p), getErasedNodeType(node))
         )
         or
         // flow through a callable
         exists(Node arg |
           parameterValueFlowCand(p, arg) and
           argumentValueFlowsThroughCand(arg, node) and
-          compatibleTypes(p.getType(), node.getType())
+          compatibleTypes(getErasedNodeType(p), getErasedNodeType(node))
         )
       }
 
@@ -95,7 +95,7 @@ private module ImplCommon {
           argumentValueFlowsThroughCand0(call, arg, kind)
         |
           out = getAnOutNode(call, kind) and
-          compatibleTypes(arg.getType(), out.getType())
+          compatibleTypes(getErasedNodeType(arg), getErasedNodeType(out))
         )
       }
 
@@ -183,7 +183,7 @@ private module ImplCommon {
         exists(Node mid |
           parameterValueFlow(p, mid, cc) and
           step(mid, node) and
-          compatibleTypes(p.getType(), node.getType()) and
+          compatibleTypes(getErasedNodeType(p), getErasedNodeType(node)) and
           not isUnreachableInCall(node, cc.(CallContextSpecificCall).getCall())
         )
         or
@@ -191,7 +191,7 @@ private module ImplCommon {
         exists(Node arg |
           parameterValueFlow(p, arg, cc) and
           argumentValueFlowsThrough(arg, node, cc) and
-          compatibleTypes(p.getType(), node.getType()) and
+          compatibleTypes(getErasedNodeType(p), getErasedNodeType(node)) and
           not isUnreachableInCall(node, cc.(CallContextSpecificCall).getCall())
         )
       }
@@ -226,7 +226,7 @@ private module ImplCommon {
         |
           out = getAnOutNode(call, kind) and
           not isUnreachableInCall(out, cc.(CallContextSpecificCall).getCall()) and
-          compatibleTypes(arg.getType(), out.getType())
+          compatibleTypes(getErasedNodeType(arg), getErasedNodeType(out))
         )
       }
     }
@@ -260,7 +260,7 @@ private module ImplCommon {
       exists(Node mid |
         parameterValueFlowNoCtx(p, mid) and
         localValueStep(mid, node) and
-        compatibleTypes(p.getType(), node.getType())
+        compatibleTypes(getErasedNodeType(p), getErasedNodeType(node))
       )
     }
 
@@ -296,8 +296,8 @@ private module ImplCommon {
         setterCall(call, i1, i2, f) and
         node1.(ArgumentNode).argumentOf(call, i1) and
         node2.getPreUpdateNode().(ArgumentNode).argumentOf(call, i2) and
-        compatibleTypes(node1.getTypeBound(), f.getType()) and
-        compatibleTypes(node2.getTypeBound(), f.getContainerType())
+        compatibleTypes(getErasedNodeTypeBound(node1), f.getType()) and
+        compatibleTypes(getErasedNodeTypeBound(node2), f.getContainerType())
       )
     }
 
@@ -333,8 +333,8 @@ private module ImplCommon {
       exists(DataFlowCall call, ReturnKind kind |
         storeReturn0(call, kind, node1, f) and
         node2 = getAnOutNode(call, kind) and
-        compatibleTypes(node1.getTypeBound(), f.getType()) and
-        compatibleTypes(node2.getTypeBound(), f.getContainerType())
+        compatibleTypes(getErasedNodeTypeBound(node1), f.getType()) and
+        compatibleTypes(getErasedNodeTypeBound(node2), f.getContainerType())
       )
     }
 
@@ -365,8 +365,8 @@ private module ImplCommon {
       exists(DataFlowCall call, ReturnKind kind |
         read0(call, kind, node1, f) and
         node2 = getAnOutNode(call, kind) and
-        compatibleTypes(node1.getTypeBound(), f.getContainerType()) and
-        compatibleTypes(node2.getTypeBound(), f.getType())
+        compatibleTypes(getErasedNodeTypeBound(node1), f.getContainerType()) and
+        compatibleTypes(getErasedNodeTypeBound(node2), f.getType())
       )
     }
 
@@ -384,7 +384,7 @@ private module ImplCommon {
         store(node1, f, mid1) and
         localValueStep*(mid1, mid2) and
         read(mid2, f, node2) and
-        compatibleTypes(node1.getTypeBound(), node2.getTypeBound())
+        compatibleTypes(getErasedNodeTypeBound(node1), getErasedNodeTypeBound(node2))
       )
     }
 
@@ -405,14 +405,14 @@ private module ImplCommon {
         exists(Node mid |
           parameterValueFlowCand(p, mid) and
           step(mid, node) and
-          compatibleTypes(p.getType(), node.getType())
+          compatibleTypes(getErasedNodeType(p), getErasedNodeType(node))
         )
         or
         // flow through a callable
         exists(Node arg |
           parameterValueFlowCand(p, arg) and
           argumentValueFlowsThroughCand(arg, node) and
-          compatibleTypes(p.getType(), node.getType())
+          compatibleTypes(getErasedNodeType(p), getErasedNodeType(node))
         )
       }
 
@@ -443,7 +443,7 @@ private module ImplCommon {
           argumentValueFlowsThroughCand0(call, arg, kind)
         |
           out = getAnOutNode(call, kind) and
-          compatibleTypes(arg.getType(), out.getType())
+          compatibleTypes(getErasedNodeType(arg), getErasedNodeType(out))
         )
       }
 
@@ -531,7 +531,7 @@ private module ImplCommon {
         exists(Node mid |
           parameterValueFlow(p, mid, cc) and
           step(mid, node) and
-          compatibleTypes(p.getType(), node.getType()) and
+          compatibleTypes(getErasedNodeType(p), getErasedNodeType(node)) and
           not isUnreachableInCall(node, cc.(CallContextSpecificCall).getCall())
         )
         or
@@ -539,7 +539,7 @@ private module ImplCommon {
         exists(Node arg |
           parameterValueFlow(p, arg, cc) and
           argumentValueFlowsThrough(arg, node, cc) and
-          compatibleTypes(p.getType(), node.getType()) and
+          compatibleTypes(getErasedNodeType(p), getErasedNodeType(node)) and
           not isUnreachableInCall(node, cc.(CallContextSpecificCall).getCall())
         )
       }
@@ -574,7 +574,7 @@ private module ImplCommon {
         |
           out = getAnOutNode(call, kind) and
           not isUnreachableInCall(out, cc.(CallContextSpecificCall).getCall()) and
-          compatibleTypes(arg.getType(), out.getType())
+          compatibleTypes(getErasedNodeType(arg), getErasedNodeType(out))
         )
       }
     }
@@ -860,4 +860,10 @@ private module ImplCommon {
     or
     result = viableCallable(call) and cc instanceof CallContextReturn
   }
+
+  pragma[noinline]
+  DataFlowType getErasedNodeType(Node n) { result = getErasedRepr(n.getType()) }
+
+  pragma[noinline]
+  DataFlowType getErasedNodeTypeBound(Node n) { result = getErasedRepr(n.getTypeBound()) }
 }

cpp/ql/src/semmle/code/cpp/ir/implementation/aliased_ssa/IRVariable.qll

@@ -13,14 +13,20 @@ IRUserVariable getIRUserVariable(Language::Function func, Language::Variable var
 }
 
 /**
- * Represents a variable referenced by the IR for a function. The variable may
- * be a user-declared variable (`IRUserVariable`) or a temporary variable
- * generated by the AST-to-IR translation (`IRTempVariable`).
+ * A variable referenced by the IR for a function. The variable may be a user-declared variable
+ * (`IRUserVariable`) or a temporary variable generated by the AST-to-IR translation
+ * (`IRTempVariable`).
  */
-abstract class IRVariable extends TIRVariable {
+class IRVariable extends TIRVariable {
   Language::Function func;
 
-  abstract string toString();
+  IRVariable() {
+    this = TIRUserVariable(_, _, func) or
+    this = TIRTempVariable(func, _, _, _) or
+    this = TIRStringLiteral(func, _, _, _)
+  }
+
+  string toString() { none() }
 
   /**
    * Holds if this variable's value cannot be changed within a function. Currently used for string
@@ -41,19 +47,19 @@ abstract class IRVariable extends TIRVariable {
   /**
    * Gets the type of the variable.
    */
-  abstract Language::LanguageType getLanguageType();
+  Language::LanguageType getLanguageType() { none() }
 
   /**
    * Gets the AST node that declared this variable, or that introduced this
    * variable as part of the AST-to-IR translation.
    */
-  abstract Language::AST getAST();
+  Language::AST getAST() { none() }
 
   /**
    * Gets an identifier string for the variable. This identifier is unique
    * within the function.
    */
-  abstract string getUniqueId();
+  string getUniqueId() { none() }
 
   /**
    * Gets the source location of this variable.
@@ -72,7 +78,7 @@ abstract class IRVariable extends TIRVariable {
 }
 
 /**
- * Represents a user-declared variable referenced by the IR for a function.
+ * A user-declared variable referenced by the IR for a function.
  */
 class IRUserVariable extends IRVariable, TIRUserVariable {
   Language::Variable var;
@@ -97,20 +103,34 @@ class IRUserVariable extends IRVariable, TIRUserVariable {
 }
 
 /**
- * Represents a variable (user-declared or temporary) that is allocated on the
- * stack. This includes all parameters, non-static local variables, and
- * temporary variables.
+ * A variable (user-declared or temporary) that is allocated on the stack. This includes all
+ * parameters, non-static local variables, and temporary variables.
  */
-abstract class IRAutomaticVariable extends IRVariable { }
+class IRAutomaticVariable extends IRVariable {
+  IRAutomaticVariable() {
+    exists(Language::Variable var |
+      this = TIRUserVariable(var, _, func) and
+      Language::isVariableAutomatic(var)
+    )
+    or
+    this = TIRTempVariable(func, _, _, _)
+  }
+}
 
+/**
+ * A user-declared variable that is allocated on the stack. This includes all parameters and
+ * non-static local variables.
+ */
 class IRAutomaticUserVariable extends IRUserVariable, IRAutomaticVariable {
   override Language::AutomaticVariable var;
 
-  IRAutomaticUserVariable() { Language::isVariableAutomatic(var) }
-
   final override Language::AutomaticVariable getVariable() { result = var }
 }
 
+/**
+ * A user-declared variable that is not allocated on the stack. This includes all global variables,
+ * namespace-scope variables, static fields, and static local variables.
+ */
 class IRStaticUserVariable extends IRUserVariable {
   override Language::StaticVariable var;
 
@@ -119,10 +139,19 @@ class IRStaticUserVariable extends IRUserVariable {
   final override Language::StaticVariable getVariable() { result = var }
 }
 
-abstract class IRGeneratedVariable extends IRVariable {
+/**
+ * A variable that is not user-declared. This includes temporary variables generated as part of IR
+ * construction, as well as string literals.
+ */
+class IRGeneratedVariable extends IRVariable {
   Language::AST ast;
   Language::LanguageType type;
 
+  IRGeneratedVariable() {
+    this = TIRTempVariable(func, ast, _, type) or
+    this = TIRStringLiteral(func, ast, type, _)
+  }
+
   final override Language::LanguageType getLanguageType() { result = type }
 
   final override Language::AST getAST() { result = ast }
@@ -144,6 +173,11 @@ IRTempVariable getIRTempVariable(Language::AST ast, TempVariableTag tag) {
   result.getTag() = tag
 }
 
+/**
+ * A temporary variable introduced by IR construction. The most common examples are the variable
+ * generated to hold the return value of afunction, or the variable generated to hold the result of
+ * a condition operator (`a ? b : c`).
+ */
 class IRTempVariable extends IRGeneratedVariable, IRAutomaticVariable, TIRTempVariable {
   TempVariableTag tag;
 
@@ -158,18 +192,28 @@ class IRTempVariable extends IRGeneratedVariable, IRAutomaticVariable, TIRTempVa
   override string getBaseString() { result = "#temp" }
 }
 
+/**
+ * A temporary variable generated to hold the return value of a function.
+ */
 class IRReturnVariable extends IRTempVariable {
   IRReturnVariable() { tag = ReturnValueTempVar() }
 
   final override string toString() { result = "#return" }
 }
 
+/**
+ * A temporary variable generated to hold the exception thrown by a `ThrowValue` instruction.
+ */
 class IRThrowVariable extends IRTempVariable {
   IRThrowVariable() { tag = ThrowTempVar() }
 
   override string getBaseString() { result = "#throw" }
 }
 
+/**
+ * A variable generated to represent the contents of a string literal. This variable acts much like
+ * a read-only global variable.
+ */
 class IRStringLiteral extends IRGeneratedVariable, TIRStringLiteral {
   Language::StringLiteral literal;
 

cpp/ql/src/semmle/code/cpp/ir/implementation/aliased_ssa/Instruction.qll

@@ -94,12 +94,21 @@ module InstructionSanity {
   /**
    * Holds if instruction `instr` has multiple operands with tag `tag`.
    */
-  query predicate duplicateOperand(Instruction instr, OperandTag tag) {
-    strictcount(NonPhiOperand operand |
-      operand = instr.getAnOperand() and
-      operand.getOperandTag() = tag
-    ) > 1 and
-    not tag instanceof UnmodeledUseOperandTag
+  query predicate duplicateOperand(
+    Instruction instr, string message, IRFunction func, string funcText
+  ) {
+    exists(OperandTag tag, int operandCount |
+      operandCount = strictcount(NonPhiOperand operand |
+          operand = instr.getAnOperand() and
+          operand.getOperandTag() = tag
+        ) and
+      operandCount > 1 and
+      not tag instanceof UnmodeledUseOperandTag and
+      message = "Instruction has " + operandCount + " operands with tag '" + tag.toString() + "'" +
+          " in function '$@'." and
+      func = instr.getEnclosingIRFunction() and
+      funcText = Language::getIdentityString(func.getFunction())
+    )
   }
 
   /**

cpp/ql/src/semmle/code/cpp/ir/implementation/aliased_ssa/internal/AliasAnalysis.qll

@@ -6,26 +6,6 @@ private import semmle.code.cpp.models.interfaces.Alias
 
 private class IntValue = Ints::IntValue;
 
-/**
- * Converts the bit count in `bits` to a byte count and a bit count in the form
- * bytes:bits.
- */
-bindingset[bits]
-string bitsToBytesAndBits(int bits) { result = (bits / 8).toString() + ":" + (bits % 8).toString() }
-
-/**
- * Gets a printable string for a bit offset with possibly unknown value.
- */
-bindingset[bitOffset]
-string getBitOffsetString(IntValue bitOffset) {
-  if Ints::hasValue(bitOffset)
-  then
-    if bitOffset >= 0
-    then result = "+" + bitsToBytesAndBits(bitOffset)
-    else result = "-" + bitsToBytesAndBits(Ints::neg(bitOffset))
-  else result = "+?"
-}
-
 /**
  * Gets the offset of field `field` in bits.
  */
@@ -137,7 +117,11 @@ private predicate operandIsPropagated(Operand operand, IntValue bitOffset) {
       or
       // Adding an integer to or subtracting an integer from a pointer propagates
       // the address with an offset.
-      bitOffset = getPointerBitOffset(instr.(PointerOffsetInstruction))
+      exists(PointerOffsetInstruction ptrOffset |
+        ptrOffset = instr and
+        operand = ptrOffset.getLeftOperand() and
+        bitOffset = getPointerBitOffset(ptrOffset)
+      )
       or
       // Computing a field address from a pointer propagates the address plus the
       // offset of the field.

cpp/ql/src/semmle/code/cpp/ir/implementation/aliased_ssa/internal/SSAConstruction.qll

@@ -865,3 +865,17 @@ private module CachedForDebugging {
     result.getTag() = var.getTag()
   }
 }
+
+module SSASanity {
+  query predicate multipleOperandMemoryLocations(
+    OldIR::MemoryOperand operand, string message, OldIR::IRFunction func, string funcText
+  ) {
+    exists(int locationCount |
+      locationCount = strictcount(Alias::getOperandMemoryLocation(operand)) and
+      locationCount > 1 and
+      func = operand.getEnclosingIRFunction() and
+      funcText = Language::getIdentityString(func.getFunction()) and
+      message = "Operand has " + locationCount.toString() + " memory accesses in function '$@'."
+    )
+  }
+}

cpp/ql/src/semmle/code/cpp/ir/implementation/aliased_ssa/internal/SSASanity.ql

@@ -0,0 +1,8 @@
+/**
+ * @name Aliased SSA Sanity Check
+ * @description Performs sanity checks on the SSA construction. This query should have no results.
+ * @kind table
+ * @id cpp/aliased-ssa-sanity-check
+ */
+
+import SSASanity

cpp/ql/src/semmle/code/cpp/ir/implementation/aliased_ssa/internal/SSASanity.qll

@@ -0,0 +1,2 @@
+private import SSAConstruction as SSA
+import SSA::SSASanity

cpp/ql/src/semmle/code/cpp/ir/implementation/raw/IRVariable.qll

@@ -13,14 +13,20 @@ IRUserVariable getIRUserVariable(Language::Function func, Language::Variable var
 }
 
 /**
- * Represents a variable referenced by the IR for a function. The variable may
- * be a user-declared variable (`IRUserVariable`) or a temporary variable
- * generated by the AST-to-IR translation (`IRTempVariable`).
+ * A variable referenced by the IR for a function. The variable may be a user-declared variable
+ * (`IRUserVariable`) or a temporary variable generated by the AST-to-IR translation
+ * (`IRTempVariable`).
  */
-abstract class IRVariable extends TIRVariable {
+class IRVariable extends TIRVariable {
   Language::Function func;
 
-  abstract string toString();
+  IRVariable() {
+    this = TIRUserVariable(_, _, func) or
+    this = TIRTempVariable(func, _, _, _) or
+    this = TIRStringLiteral(func, _, _, _)
+  }
+
+  string toString() { none() }
 
   /**
    * Holds if this variable's value cannot be changed within a function. Currently used for string
@@ -41,19 +47,19 @@ abstract class IRVariable extends TIRVariable {
   /**
    * Gets the type of the variable.
    */
-  abstract Language::LanguageType getLanguageType();
+  Language::LanguageType getLanguageType() { none() }
 
   /**
    * Gets the AST node that declared this variable, or that introduced this
    * variable as part of the AST-to-IR translation.
    */
-  abstract Language::AST getAST();
+  Language::AST getAST() { none() }
 
   /**
    * Gets an identifier string for the variable. This identifier is unique
    * within the function.
    */
-  abstract string getUniqueId();
+  string getUniqueId() { none() }
 
   /**
    * Gets the source location of this variable.
@@ -72,7 +78,7 @@ abstract class IRVariable extends TIRVariable {
 }
 
 /**
- * Represents a user-declared variable referenced by the IR for a function.
+ * A user-declared variable referenced by the IR for a function.
  */
 class IRUserVariable extends IRVariable, TIRUserVariable {
   Language::Variable var;
@@ -97,20 +103,34 @@ class IRUserVariable extends IRVariable, TIRUserVariable {
 }
 
 /**
- * Represents a variable (user-declared or temporary) that is allocated on the
- * stack. This includes all parameters, non-static local variables, and
- * temporary variables.
+ * A variable (user-declared or temporary) that is allocated on the stack. This includes all
+ * parameters, non-static local variables, and temporary variables.
  */
-abstract class IRAutomaticVariable extends IRVariable { }
+class IRAutomaticVariable extends IRVariable {
+  IRAutomaticVariable() {
+    exists(Language::Variable var |
+      this = TIRUserVariable(var, _, func) and
+      Language::isVariableAutomatic(var)
+    )
+    or
+    this = TIRTempVariable(func, _, _, _)
+  }
+}
 
+/**
+ * A user-declared variable that is allocated on the stack. This includes all parameters and
+ * non-static local variables.
+ */
 class IRAutomaticUserVariable extends IRUserVariable, IRAutomaticVariable {
   override Language::AutomaticVariable var;
 
-  IRAutomaticUserVariable() { Language::isVariableAutomatic(var) }
-
   final override Language::AutomaticVariable getVariable() { result = var }
 }
 
+/**
+ * A user-declared variable that is not allocated on the stack. This includes all global variables,
+ * namespace-scope variables, static fields, and static local variables.
+ */
 class IRStaticUserVariable extends IRUserVariable {
   override Language::StaticVariable var;
 
@@ -119,10 +139,19 @@ class IRStaticUserVariable extends IRUserVariable {
   final override Language::StaticVariable getVariable() { result = var }
 }
 
-abstract class IRGeneratedVariable extends IRVariable {
+/**
+ * A variable that is not user-declared. This includes temporary variables generated as part of IR
+ * construction, as well as string literals.
+ */
+class IRGeneratedVariable extends IRVariable {
   Language::AST ast;
   Language::LanguageType type;
 
+  IRGeneratedVariable() {
+    this = TIRTempVariable(func, ast, _, type) or
+    this = TIRStringLiteral(func, ast, type, _)
+  }
+
   final override Language::LanguageType getLanguageType() { result = type }
 
   final override Language::AST getAST() { result = ast }
@@ -144,6 +173,11 @@ IRTempVariable getIRTempVariable(Language::AST ast, TempVariableTag tag) {
   result.getTag() = tag
 }
 
+/**
+ * A temporary variable introduced by IR construction. The most common examples are the variable
+ * generated to hold the return value of afunction, or the variable generated to hold the result of
+ * a condition operator (`a ? b : c`).
+ */
 class IRTempVariable extends IRGeneratedVariable, IRAutomaticVariable, TIRTempVariable {
   TempVariableTag tag;
 
@@ -158,18 +192,28 @@ class IRTempVariable extends IRGeneratedVariable, IRAutomaticVariable, TIRTempVa
   override string getBaseString() { result = "#temp" }
 }
 
+/**
+ * A temporary variable generated to hold the return value of a function.
+ */
 class IRReturnVariable extends IRTempVariable {
   IRReturnVariable() { tag = ReturnValueTempVar() }
 
   final override string toString() { result = "#return" }
 }
 
+/**
+ * A temporary variable generated to hold the exception thrown by a `ThrowValue` instruction.
+ */
 class IRThrowVariable extends IRTempVariable {
   IRThrowVariable() { tag = ThrowTempVar() }
 
   override string getBaseString() { result = "#throw" }
 }
 
+/**
+ * A variable generated to represent the contents of a string literal. This variable acts much like
+ * a read-only global variable.
+ */
 class IRStringLiteral extends IRGeneratedVariable, TIRStringLiteral {
   Language::StringLiteral literal;
 

cpp/ql/src/semmle/code/cpp/ir/implementation/raw/Instruction.qll

@@ -94,12 +94,21 @@ module InstructionSanity {
   /**
    * Holds if instruction `instr` has multiple operands with tag `tag`.
    */
-  query predicate duplicateOperand(Instruction instr, OperandTag tag) {
-    strictcount(NonPhiOperand operand |
-      operand = instr.getAnOperand() and
-      operand.getOperandTag() = tag
-    ) > 1 and
-    not tag instanceof UnmodeledUseOperandTag
+  query predicate duplicateOperand(
+    Instruction instr, string message, IRFunction func, string funcText
+  ) {
+    exists(OperandTag tag, int operandCount |
+      operandCount = strictcount(NonPhiOperand operand |
+          operand = instr.getAnOperand() and
+          operand.getOperandTag() = tag
+        ) and
+      operandCount > 1 and
+      not tag instanceof UnmodeledUseOperandTag and
+      message = "Instruction has " + operandCount + " operands with tag '" + tag.toString() + "'" +
+          " in function '$@'." and
+      func = instr.getEnclosingIRFunction() and
+      funcText = Language::getIdentityString(func.getFunction())
+    )
   }
 
   /**

cpp/ql/src/semmle/code/cpp/ir/implementation/unaliased_ssa/IRVariable.qll

@@ -13,14 +13,20 @@ IRUserVariable getIRUserVariable(Language::Function func, Language::Variable var
 }
 
 /**
- * Represents a variable referenced by the IR for a function. The variable may
- * be a user-declared variable (`IRUserVariable`) or a temporary variable
- * generated by the AST-to-IR translation (`IRTempVariable`).
+ * A variable referenced by the IR for a function. The variable may be a user-declared variable
+ * (`IRUserVariable`) or a temporary variable generated by the AST-to-IR translation
+ * (`IRTempVariable`).
  */
-abstract class IRVariable extends TIRVariable {
+class IRVariable extends TIRVariable {
   Language::Function func;
 
-  abstract string toString();
+  IRVariable() {
+    this = TIRUserVariable(_, _, func) or
+    this = TIRTempVariable(func, _, _, _) or
+    this = TIRStringLiteral(func, _, _, _)
+  }
+
+  string toString() { none() }
 
   /**
    * Holds if this variable's value cannot be changed within a function. Currently used for string
@@ -41,19 +47,19 @@ abstract class IRVariable extends TIRVariable {
   /**
    * Gets the type of the variable.
    */
-  abstract Language::LanguageType getLanguageType();
+  Language::LanguageType getLanguageType() { none() }
 
   /**
    * Gets the AST node that declared this variable, or that introduced this
    * variable as part of the AST-to-IR translation.
    */
-  abstract Language::AST getAST();
+  Language::AST getAST() { none() }
 
   /**
    * Gets an identifier string for the variable. This identifier is unique
    * within the function.
    */
-  abstract string getUniqueId();
+  string getUniqueId() { none() }
 
   /**
    * Gets the source location of this variable.
@@ -72,7 +78,7 @@ abstract class IRVariable extends TIRVariable {
 }
 
 /**
- * Represents a user-declared variable referenced by the IR for a function.
+ * A user-declared variable referenced by the IR for a function.
  */
 class IRUserVariable extends IRVariable, TIRUserVariable {
   Language::Variable var;
@@ -97,20 +103,34 @@ class IRUserVariable extends IRVariable, TIRUserVariable {
 }
 
 /**
- * Represents a variable (user-declared or temporary) that is allocated on the
- * stack. This includes all parameters, non-static local variables, and
- * temporary variables.
+ * A variable (user-declared or temporary) that is allocated on the stack. This includes all
+ * parameters, non-static local variables, and temporary variables.
  */
-abstract class IRAutomaticVariable extends IRVariable { }
+class IRAutomaticVariable extends IRVariable {
+  IRAutomaticVariable() {
+    exists(Language::Variable var |
+      this = TIRUserVariable(var, _, func) and
+      Language::isVariableAutomatic(var)
+    )
+    or
+    this = TIRTempVariable(func, _, _, _)
+  }
+}
 
+/**
+ * A user-declared variable that is allocated on the stack. This includes all parameters and
+ * non-static local variables.
+ */
 class IRAutomaticUserVariable extends IRUserVariable, IRAutomaticVariable {
   override Language::AutomaticVariable var;
 
-  IRAutomaticUserVariable() { Language::isVariableAutomatic(var) }
-
   final override Language::AutomaticVariable getVariable() { result = var }
 }
 
+/**
+ * A user-declared variable that is not allocated on the stack. This includes all global variables,
+ * namespace-scope variables, static fields, and static local variables.
+ */
 class IRStaticUserVariable extends IRUserVariable {
   override Language::StaticVariable var;
 
@@ -119,10 +139,19 @@ class IRStaticUserVariable extends IRUserVariable {
   final override Language::StaticVariable getVariable() { result = var }
 }
 
-abstract class IRGeneratedVariable extends IRVariable {
+/**
+ * A variable that is not user-declared. This includes temporary variables generated as part of IR
+ * construction, as well as string literals.
+ */
+class IRGeneratedVariable extends IRVariable {
   Language::AST ast;
   Language::LanguageType type;
 
+  IRGeneratedVariable() {
+    this = TIRTempVariable(func, ast, _, type) or
+    this = TIRStringLiteral(func, ast, type, _)
+  }
+
   final override Language::LanguageType getLanguageType() { result = type }
 
   final override Language::AST getAST() { result = ast }
@@ -144,6 +173,11 @@ IRTempVariable getIRTempVariable(Language::AST ast, TempVariableTag tag) {
   result.getTag() = tag
 }
 
+/**
+ * A temporary variable introduced by IR construction. The most common examples are the variable
+ * generated to hold the return value of afunction, or the variable generated to hold the result of
+ * a condition operator (`a ? b : c`).
+ */
 class IRTempVariable extends IRGeneratedVariable, IRAutomaticVariable, TIRTempVariable {
   TempVariableTag tag;
 
@@ -158,18 +192,28 @@ class IRTempVariable extends IRGeneratedVariable, IRAutomaticVariable, TIRTempVa
   override string getBaseString() { result = "#temp" }
 }
 
+/**
+ * A temporary variable generated to hold the return value of a function.
+ */
 class IRReturnVariable extends IRTempVariable {
   IRReturnVariable() { tag = ReturnValueTempVar() }
 
   final override string toString() { result = "#return" }
 }
 
+/**
+ * A temporary variable generated to hold the exception thrown by a `ThrowValue` instruction.
+ */
 class IRThrowVariable extends IRTempVariable {
   IRThrowVariable() { tag = ThrowTempVar() }
 
   override string getBaseString() { result = "#throw" }
 }
 
+/**
+ * A variable generated to represent the contents of a string literal. This variable acts much like
+ * a read-only global variable.
+ */
 class IRStringLiteral extends IRGeneratedVariable, TIRStringLiteral {
   Language::StringLiteral literal;
 

cpp/ql/src/semmle/code/cpp/ir/implementation/unaliased_ssa/Instruction.qll

@@ -94,12 +94,21 @@ module InstructionSanity {
   /**
    * Holds if instruction `instr` has multiple operands with tag `tag`.
    */
-  query predicate duplicateOperand(Instruction instr, OperandTag tag) {
-    strictcount(NonPhiOperand operand |
-      operand = instr.getAnOperand() and
-      operand.getOperandTag() = tag
-    ) > 1 and
-    not tag instanceof UnmodeledUseOperandTag
+  query predicate duplicateOperand(
+    Instruction instr, string message, IRFunction func, string funcText
+  ) {
+    exists(OperandTag tag, int operandCount |
+      operandCount = strictcount(NonPhiOperand operand |
+          operand = instr.getAnOperand() and
+          operand.getOperandTag() = tag
+        ) and
+      operandCount > 1 and
+      not tag instanceof UnmodeledUseOperandTag and
+      message = "Instruction has " + operandCount + " operands with tag '" + tag.toString() + "'" +
+          " in function '$@'." and
+      func = instr.getEnclosingIRFunction() and
+      funcText = Language::getIdentityString(func.getFunction())
+    )
   }
 
   /**

cpp/ql/src/semmle/code/cpp/ir/implementation/unaliased_ssa/internal/AliasAnalysis.qll

@@ -6,26 +6,6 @@ private import semmle.code.cpp.models.interfaces.Alias
 
 private class IntValue = Ints::IntValue;
 
-/**
- * Converts the bit count in `bits` to a byte count and a bit count in the form
- * bytes:bits.
- */
-bindingset[bits]
-string bitsToBytesAndBits(int bits) { result = (bits / 8).toString() + ":" + (bits % 8).toString() }
-
-/**
- * Gets a printable string for a bit offset with possibly unknown value.
- */
-bindingset[bitOffset]
-string getBitOffsetString(IntValue bitOffset) {
-  if Ints::hasValue(bitOffset)
-  then
-    if bitOffset >= 0
-    then result = "+" + bitsToBytesAndBits(bitOffset)
-    else result = "-" + bitsToBytesAndBits(Ints::neg(bitOffset))
-  else result = "+?"
-}
-
 /**
  * Gets the offset of field `field` in bits.
  */
@@ -137,7 +117,11 @@ private predicate operandIsPropagated(Operand operand, IntValue bitOffset) {
       or
       // Adding an integer to or subtracting an integer from a pointer propagates
       // the address with an offset.
-      bitOffset = getPointerBitOffset(instr.(PointerOffsetInstruction))
+      exists(PointerOffsetInstruction ptrOffset |
+        ptrOffset = instr and
+        operand = ptrOffset.getLeftOperand() and
+        bitOffset = getPointerBitOffset(ptrOffset)
+      )
       or
       // Computing a field address from a pointer propagates the address plus the
       // offset of the field.

cpp/ql/src/semmle/code/cpp/ir/implementation/unaliased_ssa/internal/SSAConstruction.qll

@@ -865,3 +865,17 @@ private module CachedForDebugging {
     result.getTag() = var.getTag()
   }
 }
+
+module SSASanity {
+  query predicate multipleOperandMemoryLocations(
+    OldIR::MemoryOperand operand, string message, OldIR::IRFunction func, string funcText
+  ) {
+    exists(int locationCount |
+      locationCount = strictcount(Alias::getOperandMemoryLocation(operand)) and
+      locationCount > 1 and
+      func = operand.getEnclosingIRFunction() and
+      funcText = Language::getIdentityString(func.getFunction()) and
+      message = "Operand has " + locationCount.toString() + " memory accesses in function '$@'."
+    )
+  }
+}

cpp/ql/src/semmle/code/cpp/ir/implementation/unaliased_ssa/internal/SSASanity.ql

@@ -0,0 +1,8 @@
+/**
+ * @name Unaliased SSA Sanity Check
+ * @description Performs sanity checks on the SSA construction. This query should have no results.
+ * @kind table
+ * @id cpp/unaliased-ssa-sanity-check
+ */
+
+import SSASanity

cpp/ql/src/semmle/code/cpp/ir/implementation/unaliased_ssa/internal/SSASanity.qll

@@ -0,0 +1,2 @@
+private import SSAConstruction as SSA
+import SSA::SSASanity

cpp/ql/src/semmle/code/cpp/ir/internal/IntegerConstant.qll

@@ -192,3 +192,33 @@ predicate isGT(IntValue a, IntValue b) { hasValue(a) and hasValue(b) and a > b }
  */
 bindingset[a, b]
 predicate isGE(IntValue a, IntValue b) { hasValue(a) and hasValue(b) and a >= b }
+
+/**
+ * Converts the bit count in `bits` to a byte count and a bit count in the form
+ * "bytes:bits". If `bits` represents an integer number of bytes, the ":bits" section is omitted.
+ * If `bits` does not have a known value, the result is "?".
+ */
+bindingset[bits]
+string bitsToBytesAndBits(IntValue bits) {
+  exists(int bytes, int leftoverBits |
+    hasValue(bits) and
+    bytes = bits / 8 and
+    leftoverBits = bits % 8 and
+    if leftoverBits = 0 then result = bytes.toString() else result = bytes + ":" + leftoverBits
+  )
+  or
+  not hasValue(bits) and result = "?"
+}
+
+/**
+ * Gets a printable string for a bit offset with possibly unknown value.
+ */
+bindingset[bitOffset]
+string getBitOffsetString(IntValue bitOffset) {
+  if hasValue(bitOffset)
+  then
+    if bitOffset >= 0
+    then result = "+" + bitsToBytesAndBits(bitOffset)
+    else result = "-" + bitsToBytesAndBits(neg(bitOffset))
+  else result = "+?"
+}

cpp/ql/src/semmle/code/cpp/ir/internal/IntegerInterval.qll

@@ -30,5 +30,5 @@ Overlap getOverlap(IntValue defStart, IntValue defEnd, IntValue useStart, IntVal
 bindingset[start, end]
 string getIntervalString(IntValue start, IntValue end) {
   // We represent an interval has half-open, so print it as "[start..end)".
-  result = "[" + intValueToString(start) + ".." + intValueToString(end) + ")"
+  result = "[" + bitsToBytesAndBits(start) + ".." + bitsToBytesAndBits(end) + ")"
 }

cpp/ql/test/library-tests/ir/escape/points_to.expected

@@ -1,86 +1,86 @@
-| escape.cpp:111:18:111:21 | CopyValue | no_+0:0 | no_+0:0 |
-| escape.cpp:115:19:115:28 | PointerAdd[4] | no_+0:0 | no_+0:0 |
-| escape.cpp:115:20:115:23 | CopyValue | no_+0:0 | no_+0:0 |
-| escape.cpp:116:19:116:28 | PointerSub[4] | no_+0:0 | no_+0:0 |
-| escape.cpp:116:20:116:23 | CopyValue | no_+0:0 | no_+0:0 |
-| escape.cpp:117:19:117:26 | PointerAdd[4] | no_+0:0 | no_+0:0 |
-| escape.cpp:117:23:117:26 | CopyValue | no_+0:0 | no_+0:0 |
-| escape.cpp:118:9:118:12 | CopyValue | no_+0:0 | no_+0:0 |
-| escape.cpp:120:12:120:15 | CopyValue | no_+0:0 | no_+0:0 |
-| escape.cpp:123:14:123:17 | CopyValue | no_+0:0 | no_+0:0 |
-| escape.cpp:124:15:124:18 | CopyValue | no_+0:0 | no_+0:0 |
-| escape.cpp:127:9:127:12 | CopyValue | no_+0:0 | no_+0:0 |
-| escape.cpp:129:12:129:15 | CopyValue | no_+0:0 | no_+0:0 |
-| escape.cpp:134:5:134:18 | Convert | no_Array+0:0 | no_Array+0:0 |
-| escape.cpp:134:11:134:18 | Convert | no_Array+0:0 | no_Array+0:0 |
-| escape.cpp:135:5:135:12 | Convert | no_Array+0:0 | no_Array+0:0 |
-| escape.cpp:135:5:135:15 | PointerAdd[4] | no_Array+20:0 | no_Array+20:0 |
-| escape.cpp:136:5:136:15 | PointerAdd[4] | no_Array+20:0 | no_Array+20:0 |
-| escape.cpp:136:7:136:14 | Convert | no_Array+0:0 | no_Array+0:0 |
-| escape.cpp:137:17:137:24 | Convert | no_Array+0:0 | no_Array+0:0 |
-| escape.cpp:137:17:137:27 | PointerAdd[4] | no_Array+20:0 | no_Array+20:0 |
-| escape.cpp:138:17:138:27 | PointerAdd[4] | no_Array+20:0 | no_Array+20:0 |
-| escape.cpp:138:19:138:26 | Convert | no_Array+0:0 | no_Array+0:0 |
-| escape.cpp:140:21:140:32 | FieldAddress[x] | no_Point+0:0 | no_Point+0:0 |
-| escape.cpp:140:21:140:32 | FieldAddress[y] | no_Point+4:0 | no_Point+4:0 |
-| escape.cpp:140:21:140:32 | FieldAddress[z] | no_Point+8:0 | no_Point+8:0 |
-| escape.cpp:141:27:141:27 | FieldAddress[x] | no_Point+0:0 | no_Point+0:0 |
-| escape.cpp:142:14:142:14 | FieldAddress[y] | no_Point+4:0 | no_Point+4:0 |
-| escape.cpp:143:19:143:27 | CopyValue | no_Point+0:0 | no_Point+0:0 |
-| escape.cpp:143:31:143:31 | FieldAddress[y] | no_Point+4:0 | no_Point+4:0 |
-| escape.cpp:144:6:144:14 | CopyValue | no_Point+0:0 | no_Point+0:0 |
-| escape.cpp:144:18:144:18 | FieldAddress[y] | no_Point+4:0 | no_Point+4:0 |
-| escape.cpp:145:20:145:30 | CopyValue | no_Point+8:0 | no_Point+8:0 |
-| escape.cpp:145:30:145:30 | FieldAddress[z] | no_Point+8:0 | no_Point+8:0 |
-| escape.cpp:146:5:146:18 | CopyValue | no_Point+8:0 | no_Point+8:0 |
-| escape.cpp:146:7:146:17 | CopyValue | no_Point+8:0 | no_Point+8:0 |
-| escape.cpp:146:17:146:17 | FieldAddress[z] | no_Point+8:0 | no_Point+8:0 |
-| escape.cpp:149:5:149:14 | ConvertToNonVirtualBase[Derived : Intermediate1] | no_Derived+0:0 | no_Derived+0:0 |
-| escape.cpp:149:5:149:14 | ConvertToNonVirtualBase[Intermediate1 : Base] | no_Derived+0:0 | no_Derived+0:0 |
-| escape.cpp:149:16:149:16 | FieldAddress[b] | no_Derived+0:0 | no_Derived+0:0 |
-| escape.cpp:150:18:150:27 | ConvertToNonVirtualBase[Derived : Intermediate1] | no_Derived+0:0 | no_Derived+0:0 |
-| escape.cpp:150:18:150:27 | ConvertToNonVirtualBase[Intermediate1 : Base] | no_Derived+0:0 | no_Derived+0:0 |
-| escape.cpp:150:29:150:29 | FieldAddress[b] | no_Derived+0:0 | no_Derived+0:0 |
-| escape.cpp:151:5:151:14 | ConvertToNonVirtualBase[Derived : Intermediate2] | no_Derived+12:0 | no_Derived+12:0 |
-| escape.cpp:151:16:151:17 | FieldAddress[i2] | no_Derived+16:0 | no_Derived+16:0 |
-| escape.cpp:152:19:152:28 | ConvertToNonVirtualBase[Derived : Intermediate2] | no_Derived+12:0 | no_Derived+12:0 |
-| escape.cpp:152:30:152:31 | FieldAddress[i2] | no_Derived+16:0 | no_Derived+16:0 |
-| escape.cpp:155:17:155:30 | CopyValue | no_ssa_addrOf+0:0 | no_ssa_addrOf+0:0 |
-| escape.cpp:155:17:155:30 | Store | no_ssa_addrOf+0:0 | no_ssa_addrOf+0:0 |
-| escape.cpp:158:17:158:28 | CopyValue | no_ssa_refTo+0:0 | no_ssa_refTo+0:0 |
-| escape.cpp:158:17:158:28 | Store | no_ssa_refTo+0:0 | no_ssa_refTo+0:0 |
-| escape.cpp:161:19:161:42 | Convert | no_ssa_refToArrayElement+0:0 | no_ssa_refToArrayElement+0:0 |
-| escape.cpp:161:19:161:45 | CopyValue | no_ssa_refToArrayElement+20:0 | no_ssa_refToArrayElement+20:0 |
-| escape.cpp:161:19:161:45 | PointerAdd[4] | no_ssa_refToArrayElement+20:0 | no_ssa_refToArrayElement+20:0 |
-| escape.cpp:161:19:161:45 | Store | no_ssa_refToArrayElement+20:0 | no_ssa_refToArrayElement+20:0 |
-| escape.cpp:164:24:164:40 | CopyValue | no_ssa_refToArray+0:0 | no_ssa_refToArray+0:0 |
-| escape.cpp:164:24:164:40 | Store | no_ssa_refToArray+0:0 | no_ssa_refToArray+0:0 |
-| escape.cpp:167:19:167:28 | CopyValue | passByPtr+0:0 | passByPtr+0:0 |
-| escape.cpp:170:21:170:29 | CopyValue | passByRef+0:0 | passByRef+0:0 |
-| escape.cpp:173:22:173:38 | CopyValue | no_ssa_passByPtr+0:0 | no_ssa_passByPtr+0:0 |
-| escape.cpp:176:24:176:39 | CopyValue | no_ssa_passByRef+0:0 | no_ssa_passByRef+0:0 |
-| escape.cpp:179:22:179:42 | CopyValue | no_ssa_passByPtr_ret+0:0 | no_ssa_passByPtr_ret+0:0 |
-| escape.cpp:182:24:182:43 | CopyValue | no_ssa_passByRef_ret+0:0 | no_ssa_passByRef_ret+0:0 |
-| escape.cpp:185:30:185:40 | CopyValue | passByPtr2+0:0 | passByPtr2+0:0 |
-| escape.cpp:188:32:188:41 | CopyValue | passByRef2+0:0 | passByRef2+0:0 |
-| escape.cpp:191:30:191:42 | Call | none | passByPtr3+0:0 |
-| escape.cpp:191:44:191:54 | CopyValue | passByPtr3+0:0 | passByPtr3+0:0 |
-| escape.cpp:194:32:194:46 | Call | none | passByRef3+0:0 |
-| escape.cpp:194:32:194:59 | CopyValue | none | passByRef3+0:0 |
-| escape.cpp:194:48:194:57 | CopyValue | passByRef3+0:0 | passByRef3+0:0 |
-| escape.cpp:199:17:199:34 | CopyValue | no_ssa_passByPtr4+0:0 | no_ssa_passByPtr4+0:0 |
-| escape.cpp:199:37:199:54 | CopyValue | no_ssa_passByPtr5+0:0 | no_ssa_passByPtr5+0:0 |
-| escape.cpp:202:5:202:19 | Call | none | passByRef6+0:0 |
-| escape.cpp:202:5:202:32 | CopyValue | none | passByRef6+0:0 |
-| escape.cpp:202:21:202:30 | CopyValue | passByRef6+0:0 | passByRef6+0:0 |
-| escape.cpp:205:5:205:19 | Call | none | no_ssa_passByRef7+0:0 |
-| escape.cpp:205:5:205:39 | CopyValue | none | no_ssa_passByRef7+0:0 |
-| escape.cpp:205:21:205:37 | CopyValue | no_ssa_passByRef7+0:0 | no_ssa_passByRef7+0:0 |
-| escape.cpp:209:14:209:25 | Call | none | no_ssa_c+0:0 |
-| escape.cpp:217:14:217:16 | CopyValue | c2+0:0 | c2+0:0 |
-| escape.cpp:221:8:221:19 | Call | none | c3+0:0 |
-| escape.cpp:225:17:225:28 | Call | none | c4+0:0 |
-| escape.cpp:247:2:247:27 | Store | condEscape1+0:0 | condEscape1+0:0 |
-| escape.cpp:247:16:247:27 | CopyValue | condEscape1+0:0 | condEscape1+0:0 |
-| escape.cpp:249:9:249:34 | Store | condEscape2+0:0 | condEscape2+0:0 |
-| escape.cpp:249:23:249:34 | CopyValue | condEscape2+0:0 | condEscape2+0:0 |
+| escape.cpp:111:18:111:21 | CopyValue | no_+0 | no_+0 |
+| escape.cpp:115:19:115:28 | PointerAdd[4] | no_+0 | no_+0 |
+| escape.cpp:115:20:115:23 | CopyValue | no_+0 | no_+0 |
+| escape.cpp:116:19:116:28 | PointerSub[4] | no_+0 | no_+0 |
+| escape.cpp:116:20:116:23 | CopyValue | no_+0 | no_+0 |
+| escape.cpp:117:19:117:26 | PointerAdd[4] | no_+0 | no_+0 |
+| escape.cpp:117:23:117:26 | CopyValue | no_+0 | no_+0 |
+| escape.cpp:118:9:118:12 | CopyValue | no_+0 | no_+0 |
+| escape.cpp:120:12:120:15 | CopyValue | no_+0 | no_+0 |
+| escape.cpp:123:14:123:17 | CopyValue | no_+0 | no_+0 |
+| escape.cpp:124:15:124:18 | CopyValue | no_+0 | no_+0 |
+| escape.cpp:127:9:127:12 | CopyValue | no_+0 | no_+0 |
+| escape.cpp:129:12:129:15 | CopyValue | no_+0 | no_+0 |
+| escape.cpp:134:5:134:18 | Convert | no_Array+0 | no_Array+0 |
+| escape.cpp:134:11:134:18 | Convert | no_Array+0 | no_Array+0 |
+| escape.cpp:135:5:135:12 | Convert | no_Array+0 | no_Array+0 |
+| escape.cpp:135:5:135:15 | PointerAdd[4] | no_Array+20 | no_Array+20 |
+| escape.cpp:136:5:136:15 | PointerAdd[4] | no_Array+20 | no_Array+20 |
+| escape.cpp:136:7:136:14 | Convert | no_Array+0 | no_Array+0 |
+| escape.cpp:137:17:137:24 | Convert | no_Array+0 | no_Array+0 |
+| escape.cpp:137:17:137:27 | PointerAdd[4] | no_Array+20 | no_Array+20 |
+| escape.cpp:138:17:138:27 | PointerAdd[4] | no_Array+20 | no_Array+20 |
+| escape.cpp:138:19:138:26 | Convert | no_Array+0 | no_Array+0 |
+| escape.cpp:140:21:140:32 | FieldAddress[x] | no_Point+0 | no_Point+0 |
+| escape.cpp:140:21:140:32 | FieldAddress[y] | no_Point+4 | no_Point+4 |
+| escape.cpp:140:21:140:32 | FieldAddress[z] | no_Point+8 | no_Point+8 |
+| escape.cpp:141:27:141:27 | FieldAddress[x] | no_Point+0 | no_Point+0 |
+| escape.cpp:142:14:142:14 | FieldAddress[y] | no_Point+4 | no_Point+4 |
+| escape.cpp:143:19:143:27 | CopyValue | no_Point+0 | no_Point+0 |
+| escape.cpp:143:31:143:31 | FieldAddress[y] | no_Point+4 | no_Point+4 |
+| escape.cpp:144:6:144:14 | CopyValue | no_Point+0 | no_Point+0 |
+| escape.cpp:144:18:144:18 | FieldAddress[y] | no_Point+4 | no_Point+4 |
+| escape.cpp:145:20:145:30 | CopyValue | no_Point+8 | no_Point+8 |
+| escape.cpp:145:30:145:30 | FieldAddress[z] | no_Point+8 | no_Point+8 |
+| escape.cpp:146:5:146:18 | CopyValue | no_Point+8 | no_Point+8 |
+| escape.cpp:146:7:146:17 | CopyValue | no_Point+8 | no_Point+8 |
+| escape.cpp:146:17:146:17 | FieldAddress[z] | no_Point+8 | no_Point+8 |
+| escape.cpp:149:5:149:14 | ConvertToNonVirtualBase[Derived : Intermediate1] | no_Derived+0 | no_Derived+0 |
+| escape.cpp:149:5:149:14 | ConvertToNonVirtualBase[Intermediate1 : Base] | no_Derived+0 | no_Derived+0 |
+| escape.cpp:149:16:149:16 | FieldAddress[b] | no_Derived+0 | no_Derived+0 |
+| escape.cpp:150:18:150:27 | ConvertToNonVirtualBase[Derived : Intermediate1] | no_Derived+0 | no_Derived+0 |
+| escape.cpp:150:18:150:27 | ConvertToNonVirtualBase[Intermediate1 : Base] | no_Derived+0 | no_Derived+0 |
+| escape.cpp:150:29:150:29 | FieldAddress[b] | no_Derived+0 | no_Derived+0 |
+| escape.cpp:151:5:151:14 | ConvertToNonVirtualBase[Derived : Intermediate2] | no_Derived+12 | no_Derived+12 |
+| escape.cpp:151:16:151:17 | FieldAddress[i2] | no_Derived+16 | no_Derived+16 |
+| escape.cpp:152:19:152:28 | ConvertToNonVirtualBase[Derived : Intermediate2] | no_Derived+12 | no_Derived+12 |
+| escape.cpp:152:30:152:31 | FieldAddress[i2] | no_Derived+16 | no_Derived+16 |
+| escape.cpp:155:17:155:30 | CopyValue | no_ssa_addrOf+0 | no_ssa_addrOf+0 |
+| escape.cpp:155:17:155:30 | Store | no_ssa_addrOf+0 | no_ssa_addrOf+0 |
+| escape.cpp:158:17:158:28 | CopyValue | no_ssa_refTo+0 | no_ssa_refTo+0 |
+| escape.cpp:158:17:158:28 | Store | no_ssa_refTo+0 | no_ssa_refTo+0 |
+| escape.cpp:161:19:161:42 | Convert | no_ssa_refToArrayElement+0 | no_ssa_refToArrayElement+0 |
+| escape.cpp:161:19:161:45 | CopyValue | no_ssa_refToArrayElement+20 | no_ssa_refToArrayElement+20 |
+| escape.cpp:161:19:161:45 | PointerAdd[4] | no_ssa_refToArrayElement+20 | no_ssa_refToArrayElement+20 |
+| escape.cpp:161:19:161:45 | Store | no_ssa_refToArrayElement+20 | no_ssa_refToArrayElement+20 |
+| escape.cpp:164:24:164:40 | CopyValue | no_ssa_refToArray+0 | no_ssa_refToArray+0 |
+| escape.cpp:164:24:164:40 | Store | no_ssa_refToArray+0 | no_ssa_refToArray+0 |
+| escape.cpp:167:19:167:28 | CopyValue | passByPtr+0 | passByPtr+0 |
+| escape.cpp:170:21:170:29 | CopyValue | passByRef+0 | passByRef+0 |
+| escape.cpp:173:22:173:38 | CopyValue | no_ssa_passByPtr+0 | no_ssa_passByPtr+0 |
+| escape.cpp:176:24:176:39 | CopyValue | no_ssa_passByRef+0 | no_ssa_passByRef+0 |
+| escape.cpp:179:22:179:42 | CopyValue | no_ssa_passByPtr_ret+0 | no_ssa_passByPtr_ret+0 |
+| escape.cpp:182:24:182:43 | CopyValue | no_ssa_passByRef_ret+0 | no_ssa_passByRef_ret+0 |
+| escape.cpp:185:30:185:40 | CopyValue | passByPtr2+0 | passByPtr2+0 |
+| escape.cpp:188:32:188:41 | CopyValue | passByRef2+0 | passByRef2+0 |
+| escape.cpp:191:30:191:42 | Call | none | passByPtr3+0 |
+| escape.cpp:191:44:191:54 | CopyValue | passByPtr3+0 | passByPtr3+0 |
+| escape.cpp:194:32:194:46 | Call | none | passByRef3+0 |
+| escape.cpp:194:32:194:59 | CopyValue | none | passByRef3+0 |
+| escape.cpp:194:48:194:57 | CopyValue | passByRef3+0 | passByRef3+0 |
+| escape.cpp:199:17:199:34 | CopyValue | no_ssa_passByPtr4+0 | no_ssa_passByPtr4+0 |
+| escape.cpp:199:37:199:54 | CopyValue | no_ssa_passByPtr5+0 | no_ssa_passByPtr5+0 |
+| escape.cpp:202:5:202:19 | Call | none | passByRef6+0 |
+| escape.cpp:202:5:202:32 | CopyValue | none | passByRef6+0 |
+| escape.cpp:202:21:202:30 | CopyValue | passByRef6+0 | passByRef6+0 |
+| escape.cpp:205:5:205:19 | Call | none | no_ssa_passByRef7+0 |
+| escape.cpp:205:5:205:39 | CopyValue | none | no_ssa_passByRef7+0 |
+| escape.cpp:205:21:205:37 | CopyValue | no_ssa_passByRef7+0 | no_ssa_passByRef7+0 |
+| escape.cpp:209:14:209:25 | Call | none | no_ssa_c+0 |
+| escape.cpp:217:14:217:16 | CopyValue | c2+0 | c2+0 |
+| escape.cpp:221:8:221:19 | Call | none | c3+0 |
+| escape.cpp:225:17:225:28 | Call | none | c4+0 |
+| escape.cpp:247:2:247:27 | Store | condEscape1+0 | condEscape1+0 |
+| escape.cpp:247:16:247:27 | CopyValue | condEscape1+0 | condEscape1+0 |
+| escape.cpp:249:9:249:34 | Store | condEscape2+0 | condEscape2+0 |
+| escape.cpp:249:23:249:34 | CopyValue | condEscape2+0 | condEscape2+0 |

cpp/ql/test/library-tests/ir/escape/points_to.ql

@@ -4,6 +4,7 @@ import semmle.code.cpp.ir.implementation.raw.IR as Raw
 import semmle.code.cpp.ir.implementation.aliased_ssa.internal.AliasAnalysis as UnAA
 import semmle.code.cpp.ir.implementation.unaliased_ssa.IR as Un
 import semmle.code.cpp.ir.implementation.unaliased_ssa.internal.SSAConstruction
+import semmle.code.cpp.ir.internal.IntegerConstant
 
 from Raw::Instruction rawInstr, Un::Instruction unInstr, string rawPointsTo, string unPointsTo
 where
@@ -12,21 +13,21 @@ where
   (
     exists(Variable var, int rawBitOffset, int unBitOffset |
       RawAA::resultPointsTo(rawInstr, Raw::getIRUserVariable(_, var), rawBitOffset) and
-      rawPointsTo = var.toString() + RawAA::getBitOffsetString(rawBitOffset) and
+      rawPointsTo = var.toString() + getBitOffsetString(rawBitOffset) and
       UnAA::resultPointsTo(unInstr, Un::getIRUserVariable(_, var), unBitOffset) and
-      unPointsTo = var.toString() + UnAA::getBitOffsetString(unBitOffset)
+      unPointsTo = var.toString() + getBitOffsetString(unBitOffset)
     )
     or
     exists(Variable var, int unBitOffset |
       not RawAA::resultPointsTo(rawInstr, Raw::getIRUserVariable(_, var), _) and
       rawPointsTo = "none" and
       UnAA::resultPointsTo(unInstr, Un::getIRUserVariable(_, var), unBitOffset) and
-      unPointsTo = var.toString() + UnAA::getBitOffsetString(unBitOffset)
+      unPointsTo = var.toString() + getBitOffsetString(unBitOffset)
     )
     or
     exists(Variable var, int rawBitOffset |
       RawAA::resultPointsTo(rawInstr, Raw::getIRUserVariable(_, var), rawBitOffset) and
-      rawPointsTo = var.toString() + RawAA::getBitOffsetString(rawBitOffset) and
+      rawPointsTo = var.toString() + getBitOffsetString(rawBitOffset) and
       not UnAA::resultPointsTo(unInstr, Un::getIRUserVariable(_, var), _) and
       unPointsTo = "none"
     )

cpp/ql/test/library-tests/ir/ir/aliased_ssa_ssa_sanity.qlref

@@ -0,0 +1 @@
+semmle/code/cpp/ir/implementation/aliased_ssa/internal/SSASanity.ql

cpp/ql/test/library-tests/ir/ir/unaliased_ssa_ssa_sanity.qlref

@@ -0,0 +1 @@
+semmle/code/cpp/ir/implementation/unaliased_ssa/internal/SSASanity.ql

cpp/ql/test/library-tests/ir/ssa/aliased_ssa_ssa_sanity.qlref

@@ -0,0 +1 @@
+semmle/code/cpp/ir/implementation/aliased_ssa/internal/SSASanity.ql

cpp/ql/test/library-tests/ir/ssa/unaliased_ssa_ssa_sanity.qlref

@@ -0,0 +1 @@
+semmle/code/cpp/ir/implementation/unaliased_ssa/internal/SSASanity.ql

cpp/ql/test/query-tests/Security/CWE/CWE-131/semmle/NoSpaceForZeroTerminator/NoSpaceForZeroTerminator.expected

@@ -1,4 +1,6 @@
-| test.c:15:20:15:25 | call to malloc | This allocation does not include space to null-terminate the string. |
-| test.c:29:20:29:25 | call to malloc | This allocation does not include space to null-terminate the string. |
-| test.c:44:20:44:25 | call to malloc | This allocation does not include space to null-terminate the string. |
-| test.cpp:18:35:18:40 | call to malloc | This allocation does not include space to null-terminate the string. |
+| test.c:16:20:16:25 | call to malloc | This allocation does not include space to null-terminate the string. |
+| test.c:32:20:32:25 | call to malloc | This allocation does not include space to null-terminate the string. |
+| test.c:49:20:49:25 | call to malloc | This allocation does not include space to null-terminate the string. |
+| test.cpp:24:35:24:40 | call to malloc | This allocation does not include space to null-terminate the string. |
+| test.cpp:63:28:63:33 | call to malloc | This allocation does not include space to null-terminate the string. |
+| test.cpp:71:28:71:33 | call to malloc | This allocation does not include space to null-terminate the string. |

cpp/ql/test/query-tests/Security/CWE/CWE-131/semmle/NoSpaceForZeroTerminator/test.c

@@ -7,18 +7,21 @@
 typedef unsigned long size_t;
 void *malloc(size_t size);
 void free(void *ptr);
+char *strcpy(char *s1, const char *s2);
 
 //// Test code /////
 
 void bad0(char *str) {
     // BAD -- Not allocating space for '\0' terminator
     char *buffer = malloc(strlen(str));
+    strcpy(buffer, str);
     free(buffer);
 }
 
 void good0(char *str) {
     // GOOD -- Allocating extra byte for terminator
     char *buffer = malloc(strlen(str)+1);
+    strcpy(buffer, str);
     free(buffer);
 }
 
@@ -27,6 +30,7 @@ void bad1(char *str) {
     int len = strlen(str);
     // BAD -- Not allocating space for '\0' terminator
     char *buffer = malloc(len);
+    strcpy(buffer, str);
     free(buffer);
 }
 
@@ -34,6 +38,7 @@ void good1(char *str) {
     int len = strlen(str);
     // GOOD -- Allocating extra byte for terminator
     char *buffer = malloc(len+1);
+    strcpy(buffer, str);
     free(buffer);
 }
 
@@ -42,6 +47,7 @@ void bad2(char *str) {
     int len = strlen(str);
     // BAD -- Not allocating space for '\0' terminator
     char *buffer = malloc(len);
+    strcpy(buffer, str);
     free(buffer);
 }
 
@@ -49,18 +55,21 @@ void good2(char *str) {
     int len = strlen(str)+1;
     // GOOD -- Allocating extra byte for terminator
     char *buffer = malloc(len);
+    strcpy(buffer, str);
     free(buffer);
 }
 
 void bad3(char *str) {
     // BAD -- Not allocating space for '\0' terminator [NOT DETECTED]
     char *buffer = malloc(strlen(str) * sizeof(char));
+    strcpy(buffer, str);
     free(buffer);
 }
 
 void good3(char *str) {
     // GOOD -- Allocating extra byte for terminator
     char *buffer = malloc((strlen(str) + 1) * sizeof(char));
+    strcpy(buffer, str);
     free(buffer);
 }
 

cpp/ql/test/query-tests/Security/CWE/CWE-131/semmle/NoSpaceForZeroTerminator/test.cpp

@@ -10,23 +10,100 @@ typedef unsigned long size_t;
 void *malloc(size_t size);
 void free(void *ptr);
 size_t wcslen(const wchar_t *s);
+wchar_t* wcscpy(wchar_t* s1, const wchar_t* s2);
+int sprintf(char *s, const char *format, ...);
+int wprintf(const wchar_t *format, ...);
+char *strcat(char *s1, const char *s2);
+size_t strlen(const char *s);
+int strcmp(const char *s1, const char *s2);
 
 //// Test code /////
 
 void bad1(wchar_t *wstr) {
     // BAD -- Not allocating space for '\0' terminator
     wchar_t *wbuffer = (wchar_t *)malloc(wcslen(wstr));
+    wcscpy(wbuffer, wstr);
     free(wbuffer);
 }
 
 void bad2(wchar_t *wstr) {
     // BAD -- Not allocating space for '\0' terminator [NOT DETECTED]
     wchar_t *wbuffer = (wchar_t *)malloc(wcslen(wstr) * sizeof(wchar_t));
+    wcscpy(wbuffer, wstr);
     free(wbuffer);
 }
 
 void good1(wchar_t *wstr) {
     // GOOD -- Allocating extra character for terminator
     wchar_t *wbuffer = (wchar_t *)malloc((wcslen(wstr) + 1) * sizeof(wchar_t));
+    wcscpy(wbuffer, wstr);
     free(wbuffer);
 }
+
+void bad3(char *str) {
+    // BAD -- zero-termination proved by sprintf (as destination) [NOT DETECTED]
+    char *buffer = (char *)malloc(strlen(str));
+    sprintf(buffer, "%s", str);
+    free(buffer);
+}
+
+void decode(char *dest, char *src);
+void wdecode(wchar_t *dest, wchar_t *src);
+
+void bad4(char *str) {
+    // BAD -- zero-termination proved by wprintf (as parameter) [NOT DETECTED]
+    char *buffer = (char *)malloc(strlen(str));
+    decode(buffer, str);
+    wprintf(L"%s", buffer);
+    free(buffer);
+}
+
+void bad5(char *str) {
+    // BAD -- zero-termination proved by strcat (as destination)
+    char *buffer = (char *)malloc(strlen(str));
+    buffer[0] = 0;
+    strcat(buffer, str);
+    free(buffer);
+}
+
+void bad6(char *str, char *dest) {
+    // BAD -- zero-termination proved by strcat (as source)
+    char *buffer = (char *)malloc(strlen(str));
+    decode(buffer, str);
+    strcat(dest, buffer);
+    free(buffer);
+}
+
+void bad7(char *str, char *str2) {
+    // BAD -- zero-termination proved by strcmp [NOT DETECTED]
+    char *buffer = (char *)malloc(strlen(str));
+    decode(buffer, str);
+    if (strcmp(buffer, str2) == 0) {
+        // ...
+    }
+    free(buffer);
+}
+
+void bad8(wchar_t *str) {
+    // BAD -- zero-termination proved by wcslen [NOT DETECTED]
+    wchar_t *wbuffer = (wchar_t *)malloc(wcslen(str));
+    wdecode(wbuffer, str);
+    if (wcslen(wbuffer) == 0) {
+        // ...
+    }
+    free(wbuffer);
+}
+
+void good2(char *str, char *dest) {
+    // GOOD -- zero-termination not proven
+    char *buffer = (char *)malloc(strlen(str));
+    decode(buffer, str);
+    free(buffer);
+}
+
+void bad9(wchar_t *wstr) {
+    // BAD -- using new [NOT DETECTED]
+    wchar_t *wbuffer = new wchar_t[wcslen(wstr)];
+    wcscpy(wbuffer, wstr);
+    delete wbuffer;
+}

cpp/ql/test/query-tests/Security/CWE/CWE-131/semmle/NoSpaceForZeroTerminator/test2.cpp

@@ -0,0 +1,50 @@
+
+///// Library functions //////
+
+typedef unsigned long size_t;
+
+void *malloc(size_t size);
+void free(void *ptr);
+size_t strlen(const char *s);
+
+namespace std
+{
+	template<class charT> struct char_traits;
+
+	template <class T> class allocator {
+	public:
+		allocator() throw();
+		typedef size_t size_type;
+	};
+	
+	template<class charT, class traits = char_traits<charT>, class Allocator = allocator<charT> >
+	class basic_string {
+	public:
+		typedef typename Allocator::size_type size_type;
+		explicit basic_string(const Allocator& a = Allocator());
+		basic_string(const charT* s, const Allocator& a = Allocator());
+		basic_string(const charT* s, size_type n, const Allocator& a = Allocator()); 
+
+		const charT* c_str() const;
+	};
+
+	typedef basic_string<char> string;
+}
+
+//// Test code /////
+
+void bad1(char *str) {
+    // BAD -- Not allocating space for '\0' terminator [NOT DETECTED]
+    char *buffer = (char *)malloc(strlen(str));
+    std::string str2(buffer);
+    free(buffer);
+}
+
+void good1(char *str) {
+    // GOOD --- copy does not overrun due to size limit
+    char *buffer = (char *)malloc(strlen(str));
+    std::string str2(buffer, strlen(str));
+    free(buffer);
+}
+
+

csharp/autobuilder/Semmle.Autobuild.Tests/BuildScripts.cs

@@ -185,7 +185,7 @@ namespace Semmle.Extraction.Tests
         // Records the arguments passed to StartCallback.
         IList<string> StartCallbackIn = new List<string>();
 
-        void StartCallback(string s)
+        void StartCallback(string s, bool silent)
         {
             StartCallbackIn.Add(s);
         }
@@ -194,7 +194,7 @@ namespace Semmle.Extraction.Tests
         IList<string> EndCallbackIn = new List<string>();
         IList<int> EndCallbackReturn = new List<int>();
 
-        void EndCallback(int ret, string s)
+        void EndCallback(int ret, string s, bool silent)
         {
             EndCallbackReturn.Add(ret);
             EndCallbackIn.Add(s);
@@ -203,7 +203,7 @@ namespace Semmle.Extraction.Tests
         [Fact]
         public void TestBuildCommand()
         {
-            var cmd = BuildScript.Create("abc", "def ghi", null, null);
+            var cmd = BuildScript.Create("abc", "def ghi", false, null, null);
 
             Actions.RunProcess["abc def ghi"] = 1;
             cmd.Run(Actions, StartCallback, EndCallback);
@@ -216,7 +216,7 @@ namespace Semmle.Extraction.Tests
         [Fact]
         public void TestAnd1()
         {
-            var cmd = BuildScript.Create("abc", "def ghi", null, null) & BuildScript.Create("odasa", null, null, null);
+            var cmd = BuildScript.Create("abc", "def ghi", false, null, null) & BuildScript.Create("odasa", null, false, null, null);
 
             Actions.RunProcess["abc def ghi"] = 1;
             cmd.Run(Actions, StartCallback, EndCallback);
@@ -230,7 +230,7 @@ namespace Semmle.Extraction.Tests
         [Fact]
         public void TestAnd2()
         {
-            var cmd = BuildScript.Create("odasa", null, null, null) & BuildScript.Create("abc", "def ghi", null, null);
+            var cmd = BuildScript.Create("odasa", null, false, null, null) & BuildScript.Create("abc", "def ghi", false, null, null);
 
             Actions.RunProcess["abc def ghi"] = 1;
             Actions.RunProcess["odasa "] = 0;
@@ -250,7 +250,7 @@ namespace Semmle.Extraction.Tests
         [Fact]
         public void TestOr1()
         {
-            var cmd = BuildScript.Create("odasa", null, null, null) | BuildScript.Create("abc", "def ghi", null, null);
+            var cmd = BuildScript.Create("odasa", null, false, null, null) | BuildScript.Create("abc", "def ghi", false, null, null);
 
             Actions.RunProcess["abc def ghi"] = 1;
             Actions.RunProcess["odasa "] = 0;
@@ -266,7 +266,7 @@ namespace Semmle.Extraction.Tests
         [Fact]
         public void TestOr2()
         {
-            var cmd = BuildScript.Create("abc", "def ghi", null, null) | BuildScript.Create("odasa", null, null, null);
+            var cmd = BuildScript.Create("abc", "def ghi", false, null, null) | BuildScript.Create("odasa", null, false, null, null);
 
             Actions.RunProcess["abc def ghi"] = 1;
             Actions.RunProcess["odasa "] = 0;
@@ -375,7 +375,7 @@ namespace Semmle.Extraction.Tests
             Actions.RunProcess["cmd.exe /C dotnet --info"] = 0;
             Actions.RunProcess["cmd.exe /C dotnet clean test.csproj"] = 0;
             Actions.RunProcess["cmd.exe /C dotnet restore test.csproj"] = 0;
-            Actions.RunProcess[@"cmd.exe /C C:\odasa\tools\odasa index --auto dotnet build --no-incremental /p:UseSharedCompilation=false test.csproj"] = 0;
+            Actions.RunProcess[@"cmd.exe /C C:\odasa\tools\odasa index --auto dotnet build --no-incremental test.csproj"] = 0;
             Actions.RunProcess[@"cmd.exe /C C:\codeql\tools\java\bin\java -jar C:\codeql\csharp\tools\extractor-asp.jar ."] = 0;
             Actions.RunProcess[@"cmd.exe /C C:\odasa\tools\odasa index --xml --extensions config csproj props xml"] = 0;
             Actions.FileExists["csharp.log"] = true;
@@ -401,6 +401,9 @@ namespace Semmle.Extraction.Tests
         [Fact]
         public void TestLinuxCSharpAutoBuilder()
         {
+            Actions.RunProcess["dotnet --list-runtimes"] = 0;
+            Actions.RunProcessOut["dotnet --list-runtimes"] = @"Microsoft.AspNetCore.App 2.2.5 [/usr/local/share/dotnet/shared/Microsoft.AspNetCore.App]
+Microsoft.NETCore.App 2.2.5 [/usr/local/share/dotnet/shared/Microsoft.NETCore.App]";
             Actions.RunProcess["dotnet --info"] = 0;
             Actions.RunProcess["dotnet clean test.csproj"] = 0;
             Actions.RunProcess["dotnet restore test.csproj"] = 0;
@@ -424,7 +427,7 @@ namespace Semmle.Extraction.Tests
             Actions.LoadXml["test.csproj"] = xml;
 
             var autobuilder = CreateAutoBuilder("csharp", false);
-            TestAutobuilderScript(autobuilder, 0, 6);
+            TestAutobuilderScript(autobuilder, 0, 7);
         }
 
         [Fact]
@@ -598,6 +601,8 @@ namespace Semmle.Extraction.Tests
         [Fact]
         public void TestLinuxBuildCommand()
         {
+            Actions.RunProcess["dotnet --list-runtimes"] = 1;
+            Actions.RunProcessOut["dotnet --list-runtimes"] = "";
             Actions.RunProcess[@"C:\odasa/tools/odasa index --auto ""./build.sh --skip-tests"""] = 0;
             Actions.RunProcess[@"C:\codeql\tools\java/bin/java -jar C:\codeql\csharp/tools/extractor-asp.jar ."] = 0;
             Actions.RunProcess[@"C:\odasa/tools/odasa index --xml --extensions config csproj props xml"] = 0;
@@ -610,7 +615,7 @@ namespace Semmle.Extraction.Tests
             SkipVsWhere();
 
             var autobuilder = CreateAutoBuilder("csharp", false, buildCommand: "./build.sh --skip-tests");
-            TestAutobuilderScript(autobuilder, 0, 3);
+            TestAutobuilderScript(autobuilder, 0, 4);
         }
 
         [Fact]
@@ -621,6 +626,8 @@ namespace Semmle.Extraction.Tests
             Actions.GetEnvironmentVariable["CODEQL_EXTRACTOR_CSHARP_TRAP_DIR"] = "";
             Actions.GetEnvironmentVariable["CODEQL_EXTRACTOR_CSHARP_SOURCE_ARCHIVE_DIR"] = "";
             Actions.RunProcess["/bin/chmod u+x build/build.sh"] = 0;
+            Actions.RunProcess["dotnet --list-runtimes"] = 1;
+            Actions.RunProcessOut["dotnet --list-runtimes"] = "";
             Actions.RunProcess[@"C:\odasa/tools/odasa index --auto build/build.sh"] = 0;
             Actions.RunProcessWorkingDirectory[@"C:\odasa/tools/odasa index --auto build/build.sh"] = "build";
             Actions.RunProcess[@"C:\codeql\tools\java/bin/java -jar C:\codeql\csharp/tools/extractor-asp.jar ."] = 0;
@@ -628,7 +635,7 @@ namespace Semmle.Extraction.Tests
             Actions.FileExists["csharp.log"] = true;
 
             var autobuilder = CreateAutoBuilder("csharp", false);
-            TestAutobuilderScript(autobuilder, 0, 4);
+            TestAutobuilderScript(autobuilder, 0, 5);
         }
 
         [Fact]
@@ -640,12 +647,14 @@ namespace Semmle.Extraction.Tests
             Actions.GetEnvironmentVariable["CODEQL_EXTRACTOR_CSHARP_SOURCE_ARCHIVE_DIR"] = "";
 
             Actions.RunProcess["/bin/chmod u+x build.sh"] = 0;
+            Actions.RunProcess["dotnet --list-runtimes"] = 1;
+            Actions.RunProcessOut["dotnet --list-runtimes"] = "";
             Actions.RunProcess[@"C:\odasa/tools/odasa index --auto build.sh"] = 0;
             Actions.RunProcessWorkingDirectory[@"C:\odasa/tools/odasa index --auto build.sh"] = "";
             Actions.FileExists["csharp.log"] = false;
 
             var autobuilder = CreateAutoBuilder("csharp", false);
-            TestAutobuilderScript(autobuilder, 1, 2);
+            TestAutobuilderScript(autobuilder, 1, 3);
         }
 
         [Fact]
@@ -657,12 +666,14 @@ namespace Semmle.Extraction.Tests
             Actions.GetEnvironmentVariable["CODEQL_EXTRACTOR_CSHARP_SOURCE_ARCHIVE_DIR"] = "";
 
             Actions.RunProcess["/bin/chmod u+x build.sh"] = 0;
+            Actions.RunProcess["dotnet --list-runtimes"] = 1;
+            Actions.RunProcessOut["dotnet --list-runtimes"] = "";
             Actions.RunProcess[@"C:\odasa/tools/odasa index --auto build.sh"] = 5;
             Actions.RunProcessWorkingDirectory[@"C:\odasa/tools/odasa index --auto build.sh"] = "";
             Actions.FileExists["csharp.log"] = true;
 
             var autobuilder = CreateAutoBuilder("csharp", false);
-            TestAutobuilderScript(autobuilder, 1, 2);
+            TestAutobuilderScript(autobuilder, 1, 3);
         }
 
         [Fact]
@@ -748,7 +759,7 @@ namespace Semmle.Extraction.Tests
             TestAutobuilderScript(autobuilder, 0, 6);
         }
 
-    [Fact]
+        [Fact]
         public void TestWindowCSharpMsBuildMultipleSolutions()
         {
             Actions.RunProcess[@"cmd.exe /C C:\odasa\tools\csharp\nuget\nuget.exe restore test1.csproj"] = 0;
@@ -871,6 +882,9 @@ namespace Semmle.Extraction.Tests
         [Fact]
         public void TestSkipNugetDotnet()
         {
+            Actions.RunProcess["dotnet --list-runtimes"] = 0;
+            Actions.RunProcessOut["dotnet --list-runtimes"] = @"Microsoft.AspNetCore.App 2.1.3 [/usr/local/share/dotnet/shared/Microsoft.AspNetCore.App]
+Microsoft.NETCore.App 2.1.3 [/usr/local/share/dotnet/shared/Microsoft.NETCore.App]";
             Actions.RunProcess["dotnet --info"] = 0;
             Actions.RunProcess["dotnet clean test.csproj"] = 0;
             Actions.RunProcess["dotnet restore test.csproj"] = 0;
@@ -894,7 +908,7 @@ namespace Semmle.Extraction.Tests
             Actions.LoadXml["test.csproj"] = xml;
 
             var autobuilder = CreateAutoBuilder("csharp", false, dotnetArguments: "--no-restore");  // nugetRestore=false does not work for now.
-            TestAutobuilderScript(autobuilder, 0, 6);
+            TestAutobuilderScript(autobuilder, 0, 7);
         }
 
         [Fact]
@@ -906,10 +920,13 @@ namespace Semmle.Extraction.Tests
             Actions.RunProcess[@"chmod u+x dotnet-install.sh"] = 0;
             Actions.RunProcess[@"./dotnet-install.sh --channel release --version 2.1.3 --install-dir C:\Project/.dotnet"] = 0;
             Actions.RunProcess[@"rm dotnet-install.sh"] = 0;
+            Actions.RunProcess[@"C:\Project/.dotnet/dotnet --list-runtimes"] = 0;
+            Actions.RunProcessOut[@"C:\Project/.dotnet/dotnet --list-runtimes"] = @"Microsoft.AspNetCore.App 3.0.0 [/usr/local/share/dotnet/shared/Microsoft.AspNetCore.App]
+Microsoft.NETCore.App 3.0.0 [/usr/local/share/dotnet/shared/Microsoft.NETCore.App]";
             Actions.RunProcess[@"C:\Project/.dotnet/dotnet --info"] = 0;
             Actions.RunProcess[@"C:\Project/.dotnet/dotnet clean test.csproj"] = 0;
             Actions.RunProcess[@"C:\Project/.dotnet/dotnet restore test.csproj"] = 0;
-            Actions.RunProcess[@"C:\odasa/tools/odasa index --auto C:\Project/.dotnet/dotnet build --no-incremental /p:UseSharedCompilation=false test.csproj"] = 0;
+            Actions.RunProcess[@"C:\odasa/tools/odasa index --auto C:\Project/.dotnet/dotnet build --no-incremental test.csproj"] = 0;
             Actions.RunProcess[@"C:\codeql\tools\java/bin/java -jar C:\codeql\csharp/tools/extractor-asp.jar ."] = 0;
             Actions.RunProcess[@"C:\odasa/tools/odasa index --xml --extensions config csproj props xml"] = 0;
             Actions.FileExists["csharp.log"] = true;
@@ -930,18 +947,24 @@ namespace Semmle.Extraction.Tests
             Actions.LoadXml["test.csproj"] = xml;
 
             var autobuilder = CreateAutoBuilder("csharp", false, dotnetVersion: "2.1.3");
-            TestAutobuilderScript(autobuilder, 0, 11);
+            TestAutobuilderScript(autobuilder, 0, 12);
         }
 
         [Fact]
         public void TestDotnetVersionAlreadyInstalled()
         {
             Actions.RunProcess["dotnet --list-sdks"] = 0;
-            Actions.RunProcessOut["dotnet --list-sdks"] = "2.1.3 [C:\\Program Files\\dotnet\\sdks]\n2.1.4 [C:\\Program Files\\dotnet\\sdks]";
+            Actions.RunProcessOut["dotnet --list-sdks"] = @"2.1.3 [C:\Program Files\dotnet\sdks]
+2.1.4 [C:\Program Files\dotnet\sdks]";
             Actions.RunProcess[@"curl -L -sO https://dot.net/v1/dotnet-install.sh"] = 0;
             Actions.RunProcess[@"chmod u+x dotnet-install.sh"] = 0;
             Actions.RunProcess[@"./dotnet-install.sh --channel release --version 2.1.3 --install-dir C:\Project/.dotnet"] = 0;
             Actions.RunProcess[@"rm dotnet-install.sh"] = 0;
+            Actions.RunProcess[@"C:\Project/.dotnet/dotnet --list-runtimes"] = 0;
+            Actions.RunProcessOut[@"C:\Project/.dotnet/dotnet --list-runtimes"] = @"Microsoft.AspNetCore.App 2.1.3 [/usr/local/share/dotnet/shared/Microsoft.AspNetCore.App]
+Microsoft.AspNetCore.App 2.1.4 [/usr/local/share/dotnet/shared/Microsoft.AspNetCore.App]
+Microsoft.NETCore.App 2.1.3 [/usr/local/share/dotnet/shared/Microsoft.NETCore.App]
+Microsoft.NETCore.App 2.1.4 [/usr/local/share/dotnet/shared/Microsoft.NETCore.App]";
             Actions.RunProcess[@"C:\Project/.dotnet/dotnet --info"] = 0;
             Actions.RunProcess[@"C:\Project/.dotnet/dotnet clean test.csproj"] = 0;
             Actions.RunProcess[@"C:\Project/.dotnet/dotnet restore test.csproj"] = 0;
@@ -966,7 +989,7 @@ namespace Semmle.Extraction.Tests
             Actions.LoadXml["test.csproj"] = xml;
 
             var autobuilder = CreateAutoBuilder("csharp", false, dotnetVersion: "2.1.3");
-            TestAutobuilderScript(autobuilder, 0, 11);
+            TestAutobuilderScript(autobuilder, 0, 12);
         }
 
         [Fact]
@@ -979,7 +1002,7 @@ namespace Semmle.Extraction.Tests
             Actions.RunProcess[@"cmd.exe /C C:\Project\.dotnet\dotnet --info"] = 0;
             Actions.RunProcess[@"cmd.exe /C C:\Project\.dotnet\dotnet clean test.csproj"] = 0;
             Actions.RunProcess[@"cmd.exe /C C:\Project\.dotnet\dotnet restore test.csproj"] = 0;
-            Actions.RunProcess[@"cmd.exe /C C:\odasa\tools\odasa index --auto C:\Project\.dotnet\dotnet build --no-incremental /p:UseSharedCompilation=false test.csproj"] = 0;
+            Actions.RunProcess[@"cmd.exe /C C:\odasa\tools\odasa index --auto C:\Project\.dotnet\dotnet build --no-incremental test.csproj"] = 0;
             Actions.RunProcess[@"cmd.exe /C C:\codeql\tools\java\bin\java -jar C:\codeql\csharp\tools\extractor-asp.jar ."] = 0;
             Actions.RunProcess[@"cmd.exe /C C:\odasa\tools\odasa index --xml --extensions config csproj props xml"] = 0;
             Actions.FileExists["csharp.log"] = true;

csharp/autobuilder/Semmle.Autobuild/Autobuilder.cs

@@ -214,8 +214,16 @@ namespace Semmle.Autobuild
             if (Options.IgnoreErrors)
                 script |= BuildScript.Success;
 
-            void startCallback(string s) => Log(Severity.Info, $"\nRunning {s}");
-            void exitCallback(int ret, string msg) => Log(Severity.Info, $"Exit code {ret}{(string.IsNullOrEmpty(msg) ? "" : $": {msg}")}");
+            void startCallback(string s, bool silent)
+            {
+                Log(silent ? Severity.Debug : Severity.Info, $"\nRunning {s}");
+            }
+
+            void exitCallback(int ret, string msg, bool silent)
+            {
+                Log(silent ? Severity.Debug : Severity.Info, $"Exit code {ret}{(string.IsNullOrEmpty(msg) ? "" : $": {msg}")}");
+            }
+
             return script.Run(Actions, startCallback, exitCallback);
         }
 

csharp/autobuilder/Semmle.Autobuild/BuildActions.cs

@@ -141,12 +141,8 @@ namespace Semmle.Autobuild
                 pi.WorkingDirectory = workingDirectory;
 
             // Environment variables can only be used when not redirecting stdout
-            if (!redirectStandardOutput)
-            {
-                pi.Environment["UseSharedCompilation"] = "false";
-                if (environment != null)
-                    environment.ForEach(kvp => pi.Environment[kvp.Key] = kvp.Value);
-            }
+            if (!redirectStandardOutput && environment != null)
+                environment.ForEach(kvp => pi.Environment[kvp.Key] = kvp.Value);
             return pi;
         }
 

csharp/autobuilder/Semmle.Autobuild/BuildCommandAutoRule.cs

@@ -43,9 +43,9 @@ namespace Semmle.Autobuild
             var dir = Path.GetDirectoryName(scriptPath);
 
             // A specific .NET Core version may be required
-            return chmodScript & DotNetRule.WithDotNet(builder, dotNet =>
+            return chmodScript & DotNetRule.WithDotNet(builder, environment =>
             {
-                var command = new CommandBuilder(builder.Actions, dir, dotNet?.Environment);
+                var command = new CommandBuilder(builder.Actions, dir, environment);
 
                 // A specific Visual Studio version may be required
                 var vsTools = MsBuildRule.GetVcVarsBatFile(builder);

csharp/autobuilder/Semmle.Autobuild/BuildCommandRule.cs

@@ -11,9 +11,9 @@
                 return BuildScript.Failure;
 
             // Custom build commands may require a specific .NET Core version
-            return DotNetRule.WithDotNet(builder, dotNet =>
+            return DotNetRule.WithDotNet(builder, environment =>
                 {
-                    var command = new CommandBuilder(builder.Actions, null, dotNet?.Environment);
+                    var command = new CommandBuilder(builder.Actions, null, environment);
 
                     // Custom build commands may require a specific Visual Studio version
                     var vsTools = MsBuildRule.GetVcVarsBatFile(builder);

csharp/autobuilder/Semmle.Autobuild/BuildScript.cs

@@ -25,7 +25,7 @@ namespace Semmle.Autobuild
         /// an exit message.
         /// </param>
         /// <returns>The exit code from this build script.</returns>
-        public abstract int Run(IBuildActions actions, Action<string> startCallback, Action<int, string> exitCallBack);
+        public abstract int Run(IBuildActions actions, Action<string, bool> startCallback, Action<int, string, bool> exitCallBack);
 
         /// <summary>
         /// Run this build command.
@@ -44,33 +44,36 @@ namespace Semmle.Autobuild
         /// </param>
         /// <param name="stdout">Contents of standard out.</param>
         /// <returns>The exit code from this build script.</returns>
-        public abstract int Run(IBuildActions actions, Action<string> startCallback, Action<int, string> exitCallBack, out IList<string> stdout);
+        public abstract int Run(IBuildActions actions, Action<string, bool> startCallback, Action<int, string, bool> exitCallBack, out IList<string> stdout);
 
         class BuildCommand : BuildScript
         {
             readonly string exe, arguments, workingDirectory;
             readonly IDictionary<string, string> environment;
+            readonly bool silent;
 
             /// <summary>
             /// Create a simple build command.
             /// </summary>
             /// <param name="exe">The executable to run.</param>
             /// <param name="argumentsOpt">The arguments to the executable, or null.</param>
+            /// <param name="silent">Whether this command should run silently.</param>
             /// <param name="workingDirectory">The working directory (<code>null</code> for current directory).</param>
             /// <param name="environment">Additional environment variables.</param>
-            public BuildCommand(string exe, string argumentsOpt, string workingDirectory = null, IDictionary<string, string> environment = null)
+            public BuildCommand(string exe, string argumentsOpt, bool silent, string workingDirectory = null, IDictionary<string, string> environment = null)
             {
                 this.exe = exe;
                 this.arguments = argumentsOpt ?? "";
+                this.silent = silent;
                 this.workingDirectory = workingDirectory;
                 this.environment = environment;
             }
 
             public override string ToString() => exe + " " + arguments;
 
-            public override int Run(IBuildActions actions, Action<string> startCallback, Action<int, string> exitCallBack)
+            public override int Run(IBuildActions actions, Action<string, bool> startCallback, Action<int, string, bool> exitCallBack)
             {
-                startCallback(this.ToString());
+                startCallback(this.ToString(), silent);
                 var ret = 1;
                 var retMessage = "";
                 try
@@ -83,13 +86,13 @@ namespace Semmle.Autobuild
                     retMessage = ex.Message;
                 }
 
-                exitCallBack(ret, retMessage);
+                exitCallBack(ret, retMessage, silent);
                 return ret;
             }
 
-            public override int Run(IBuildActions actions, Action<string> startCallback, Action<int, string> exitCallBack, out IList<string> stdout)
+            public override int Run(IBuildActions actions, Action<string, bool> startCallback, Action<int, string, bool> exitCallBack, out IList<string> stdout)
             {
-                startCallback(this.ToString());
+                startCallback(this.ToString(), silent);
                 var ret = 1;
                 var retMessage = "";
                 try
@@ -102,7 +105,7 @@ namespace Semmle.Autobuild
                     retMessage = ex.Message;
                     stdout = new string[0];
                 }
-                exitCallBack(ret, retMessage);
+                exitCallBack(ret, retMessage, silent);
                 return ret;
             }
 
@@ -116,9 +119,9 @@ namespace Semmle.Autobuild
                 this.func = func;
             }
 
-            public override int Run(IBuildActions actions, Action<string> startCallback, Action<int, string> exitCallBack) => func(actions);
+            public override int Run(IBuildActions actions, Action<string, bool> startCallback, Action<int, string, bool> exitCallBack) => func(actions);
 
-            public override int Run(IBuildActions actions, Action<string> startCallback, Action<int, string> exitCallBack, out IList<string> stdout)
+            public override int Run(IBuildActions actions, Action<string, bool> startCallback, Action<int, string, bool> exitCallBack, out IList<string> stdout)
             {
                 stdout = new string[0];
                 return func(actions);
@@ -142,7 +145,7 @@ namespace Semmle.Autobuild
                 this.s2b = s2;
             }
 
-            public override int Run(IBuildActions actions, Action<string> startCallback, Action<int, string> exitCallBack)
+            public override int Run(IBuildActions actions, Action<string, bool> startCallback, Action<int, string, bool> exitCallBack)
             {
                 int ret1;
                 if (s2a != null)
@@ -155,7 +158,7 @@ namespace Semmle.Autobuild
                 return s2b(ret1).Run(actions, startCallback, exitCallBack);
             }
 
-            public override int Run(IBuildActions actions, Action<string> startCallback, Action<int, string> exitCallBack, out IList<string> stdout)
+            public override int Run(IBuildActions actions, Action<string, bool> startCallback, Action<int, string, bool> exitCallBack, out IList<string> stdout)
             {
                 var ret1 = s1.Run(actions, startCallback, exitCallBack, out var stdout1);
                 var ret2 = (s2a != null ? s2a(stdout1, ret1) : s2b(ret1)).Run(actions, startCallback, exitCallBack, out var stdout2);
@@ -171,10 +174,11 @@ namespace Semmle.Autobuild
         /// Creates a simple build script that runs the specified exe.
         /// </summary>
         /// <param name="argumentsOpt">The arguments to the executable, or null.</param>
+        /// <param name="silent">Whether the executable should run silently.</param>
         /// <param name="workingDirectory">The working directory (<code>null</code> for current directory).</param>
         /// <param name="environment">Additional environment variables.</param>
-        public static BuildScript Create(string exe, string argumentsOpt, string workingDirectory, IDictionary<string, string> environment) =>
-            new BuildCommand(exe, argumentsOpt, workingDirectory, environment);
+        public static BuildScript Create(string exe, string argumentsOpt, bool silent, string workingDirectory, IDictionary<string, string> environment) =>
+            new BuildCommand(exe, argumentsOpt, silent, workingDirectory, environment);
 
         /// <summary>
         /// Creates a simple build script that runs the specified function.

csharp/autobuilder/Semmle.Autobuild/CommandBuilder.cs

@@ -17,13 +17,15 @@ namespace Semmle.Autobuild
         readonly EscapeMode escapingMode;
         readonly string workingDirectory;
         readonly IDictionary<string, string> environment;
+        readonly bool silent;
 
         /// <summary>
         /// Initializes a new instance of the <see cref="T:Semmle.Autobuild.CommandBuilder"/> class.
         /// </summary>
         /// <param name="workingDirectory">The working directory (<code>null</code> for current directory).</param>
         /// <param name="environment">Additional environment variables.</param>
-        public CommandBuilder(IBuildActions actions, string workingDirectory = null, IDictionary<string, string> environment = null)
+        /// <param name="silent">Whether this command should be run silently.</param>
+        public CommandBuilder(IBuildActions actions, string workingDirectory = null, IDictionary<string, string> environment = null, bool silent = false)
         {
             arguments = new StringBuilder();
             if (actions.IsWindows())
@@ -40,6 +42,7 @@ namespace Semmle.Autobuild
             firstCommand = true;
             this.workingDirectory = workingDirectory;
             this.environment = environment;
+            this.silent = silent;
         }
 
         void OdasaIndex(string odasa)
@@ -190,6 +193,6 @@ namespace Semmle.Autobuild
         /// <summary>
         /// Returns a build script that contains just this command.
         /// </summary>
-        public BuildScript Script => BuildScript.Create(executable, arguments.ToString(), workingDirectory, environment);
+        public BuildScript Script => BuildScript.Create(executable, arguments.ToString(), silent, workingDirectory, environment);
     }
 }

csharp/autobuilder/Semmle.Autobuild/DotNetRule.cs

@@ -5,6 +5,7 @@ using Newtonsoft.Json.Linq;
 using System.Collections.Generic;
 using System.IO;
 using Semmle.Util;
+using System.Text.RegularExpressions;
 
 namespace Semmle.Autobuild
 {
@@ -34,22 +35,20 @@ namespace Semmle.Autobuild
                 builder.Log(Severity.Info, "Attempting to build using .NET Core");
             }
 
-            return WithDotNet(builder, dotNet =>
+            return WithDotNet(builder, (dotNetPath, environment, compatibleClr) =>
                 {
-                    var ret = GetInfoCommand(builder.Actions, dotNet);
+                    var ret = GetInfoCommand(builder.Actions, dotNetPath, environment);
                     foreach (var projectOrSolution in builder.ProjectsOrSolutionsToBuild)
                     {
-                        var cleanCommand = GetCleanCommand(builder.Actions, dotNet);
+                        var cleanCommand = GetCleanCommand(builder.Actions, dotNetPath, environment);
                         cleanCommand.QuoteArgument(projectOrSolution.FullPath);
                         var clean = cleanCommand.Script;
 
-                        var restoreCommand = GetRestoreCommand(builder.Actions, dotNet);
+                        var restoreCommand = GetRestoreCommand(builder.Actions, dotNetPath, environment);
                         restoreCommand.QuoteArgument(projectOrSolution.FullPath);
                         var restore = restoreCommand.Script;
 
-                        var buildCommand = GetBuildCommand(builder, dotNet);
-                        buildCommand.QuoteArgument(projectOrSolution.FullPath);
-                        var build = buildCommand.Script;
+                        var build = GetBuildScript(builder, dotNetPath, environment, compatibleClr, projectOrSolution.FullPath);
 
                         ret &= clean & BuildScript.Try(restore) & build;
                     }
@@ -57,38 +56,73 @@ namespace Semmle.Autobuild
                 });
         }
 
-        /// <summary>
-        /// Returns a script that attempts to download relevant version(s) of the
-        /// .NET Core SDK, followed by running the script generated by <paramref name="f"/>.
-        ///
-        /// The first element <code>DotNetPath</code> of the argument to <paramref name="f"/>
-        /// is the path where .NET Core was installed, and the second element <code>Environment</code>
-        /// is any additional required environment variables. The tuple argument is <code>null</code>
-        /// when the installation failed.
-        /// </summary>
-        public static BuildScript WithDotNet(Autobuilder builder, Func<(string DotNetPath, IDictionary<string, string> Environment)?, BuildScript> f)
+        static BuildScript WithDotNet(Autobuilder builder, Func<string, IDictionary<string, string>, bool, BuildScript> f)
         {
             var installDir = builder.Actions.PathCombine(builder.Options.RootDirectory, ".dotnet");
             var installScript = DownloadDotNet(builder, installDir);
             return BuildScript.Bind(installScript, installed =>
+            {
+                Dictionary<string, string> env;
+                if (installed == 0)
                 {
-                    if (installed == 0)
-                    {
-                        // The installation succeeded, so use the newly installed .NET Core
-                        var path = builder.Actions.GetEnvironmentVariable("PATH");
-                        var delim = builder.Actions.IsWindows() ? ";" : ":";
-                        var env = new Dictionary<string, string>{
+                    // The installation succeeded, so use the newly installed .NET Core
+                    var path = builder.Actions.GetEnvironmentVariable("PATH");
+                    var delim = builder.Actions.IsWindows() ? ";" : ":";
+                    env = new Dictionary<string, string>{
                             { "DOTNET_MULTILEVEL_LOOKUP", "false" }, // prevent look up of other .NET Core SDKs
                             { "DOTNET_SKIP_FIRST_TIME_EXPERIENCE", "true" },
                             { "PATH", installDir + delim + path }
                         };
-                        return f((installDir, env));
+                }
+                else
+                {
+                    installDir = null;
+                    env = null;
+                }
+
+                // The CLR tracer is always compatible on Windows
+                if (builder.Actions.IsWindows())
+                    return f(installDir, env, true);
+
+                // The CLR tracer is only compatible on .NET Core >= 3 on Linux and macOS (see
+                // https://github.com/dotnet/coreclr/issues/19622)
+                return BuildScript.Bind(GetInstalledRuntimesScript(builder.Actions, installDir, env), (runtimes, runtimesRet) =>
+                {
+                    var compatibleClr = false;
+                    if (runtimesRet == 0)
+                    {
+                        var minimumVersion = new Version(3, 0);
+                        var regex = new Regex(@"Microsoft\.NETCore\.App (\d\.\d\.\d)");
+                        compatibleClr = runtimes.
+                            Select(runtime => regex.Match(runtime)).
+                            Where(m => m.Success).
+                            Select(m => m.Groups[1].Value).
+                            Any(m => Version.TryParse(m, out var v) && v >= minimumVersion);
                     }
 
-                    return f(null);
+                    if (!compatibleClr)
+                    {
+                        if (env == null)
+                            env = new Dictionary<string, string>();
+                        env.Add("UseSharedCompilation", "false");
+                    }
+
+                    return f(installDir, env, compatibleClr);
                 });
+            });
         }
 
+        /// <summary>
+        /// Returns a script that attempts to download relevant version(s) of the
+        /// .NET Core SDK, followed by running the script generated by <paramref name="f"/>.
+        ///
+        /// The argument to <paramref name="f"/> is any additional required environment
+        /// variables needed by the installed .NET Core (<code>null</code> when no variables
+        /// are needed).
+        /// </summary>
+        public static BuildScript WithDotNet(Autobuilder builder, Func<IDictionary<string, string>, BuildScript> f)
+            => WithDotNet(builder, (_1, env, _2) => f(env));
+
         /// <summary>
         /// Returns a script for downloading relevant versions of the
         /// .NET Core SDK. The SDK(s) will be installed at <code>installDir</code>
@@ -225,7 +259,7 @@ Invoke-Command -ScriptBlock $ScriptBlock";
 
         static BuildScript GetInstalledSdksScript(IBuildActions actions)
         {
-            var listSdks = new CommandBuilder(actions).
+            var listSdks = new CommandBuilder(actions, silent: true).
                 RunCommand("dotnet").
                 Argument("--list-sdks");
             return listSdks.Script;
@@ -234,38 +268,62 @@ Invoke-Command -ScriptBlock $ScriptBlock";
         static string DotNetCommand(IBuildActions actions, string dotNetPath) =>
             dotNetPath != null ? actions.PathCombine(dotNetPath, "dotnet") : "dotnet";
 
-        BuildScript GetInfoCommand(IBuildActions actions, (string DotNetPath, IDictionary<string, string> Environment)? arg)
+        BuildScript GetInfoCommand(IBuildActions actions, string dotNetPath, IDictionary<string, string> environment)
         {
-            var info = new CommandBuilder(actions, null, arg?.Environment).
-                RunCommand(DotNetCommand(actions, arg?.DotNetPath)).
+            var info = new CommandBuilder(actions, null, environment).
+                RunCommand(DotNetCommand(actions, dotNetPath)).
                 Argument("--info");
             return info.Script;
         }
 
-        CommandBuilder GetCleanCommand(IBuildActions actions, (string DotNetPath, IDictionary<string, string> Environment)? arg)
+        CommandBuilder GetCleanCommand(IBuildActions actions, string dotNetPath, IDictionary<string, string> environment)
         {
-            var clean = new CommandBuilder(actions, null, arg?.Environment).
-                RunCommand(DotNetCommand(actions, arg?.DotNetPath)).
+            var clean = new CommandBuilder(actions, null, environment).
+                RunCommand(DotNetCommand(actions, dotNetPath)).
                 Argument("clean");
             return clean;
         }
 
-        CommandBuilder GetRestoreCommand(IBuildActions actions, (string DotNetPath, IDictionary<string, string> Environment)? arg)
+        CommandBuilder GetRestoreCommand(IBuildActions actions, string dotNetPath, IDictionary<string, string> environment)
         {
-            var restore = new CommandBuilder(actions, null, arg?.Environment).
-                RunCommand(DotNetCommand(actions, arg?.DotNetPath)).
+            var restore = new CommandBuilder(actions, null, environment).
+                RunCommand(DotNetCommand(actions, dotNetPath)).
                 Argument("restore");
             return restore;
         }
 
-        CommandBuilder GetBuildCommand(Autobuilder builder, (string DotNetPath, IDictionary<string, string> Environment)? arg)
+        static BuildScript GetInstalledRuntimesScript(IBuildActions actions, string dotNetPath, IDictionary<string, string> environment)
         {
-            var build = new CommandBuilder(builder.Actions, null, arg?.Environment);
-            return builder.MaybeIndex(build, DotNetCommand(builder.Actions, arg?.DotNetPath)).
+            var listSdks = new CommandBuilder(actions, environment: environment, silent: true).
+                RunCommand(DotNetCommand(actions, dotNetPath)).
+                Argument("--list-runtimes");
+            return listSdks.Script;
+        }
+
+        /// <summary>
+        /// Gets the `dotnet build` script.
+        ///
+        /// The CLR tracer only works on .NET Core >= 3 on Linux and macOS (see
+        /// https://github.com/dotnet/coreclr/issues/19622), so in case we are
+        /// running on an older .NET Core, we disable shared compilation (and
+        /// hence the need for CLR tracing), by adding a
+        /// `/p:UseSharedCompilation=false` argument.
+        /// </summary>
+        BuildScript GetBuildScript(Autobuilder builder, string dotNetPath, IDictionary<string, string> environment, bool compatibleClr, string projOrSln)
+        {
+            var build = new CommandBuilder(builder.Actions, null, environment);
+            var script = builder.MaybeIndex(build, DotNetCommand(builder.Actions, dotNetPath)).
                 Argument("build").
-                Argument("--no-incremental").
-                Argument("/p:UseSharedCompilation=false").
-                Argument(builder.Options.DotNetArguments);
+                Argument("--no-incremental");
+
+            return compatibleClr ?
+                script.Argument(builder.Options.DotNetArguments).
+                    QuoteArgument(projOrSln).
+                    Script :
+                script.Argument("/p:UseSharedCompilation=false").
+                    Argument(builder.Options.DotNetArguments).
+                    QuoteArgument(projOrSln).
+                    Script;
         }
     }
 }

csharp/ql/src/Security Features/CWE-016/ASPNetMaxRequestLength.qhelp

@@ -0,0 +1,47 @@
+<!DOCTYPE qhelp PUBLIC
+  "-//Semmle//qhelp//EN"
+  "qhelp.dtd">
+<qhelp>
+
+  <overview>
+    <p>
+      The <code>maxRequestLength</code> attribute sets the limit for the input
+      stream buffering threshold in KB. Attackers can use large requests to cause
+      denial-of-service attacks.
+    </p>
+  </overview>
+  <recommendation>
+
+    <p>
+      The recommended value is 4096 KB but you should try setting it as
+      small as possible according to business requirements.
+    </p>
+
+  </recommendation>
+  <example>
+
+    <p>
+      The following example shows the <code>maxRequestLength</code>
+      attribute set to a high value (255 MB) in a <code>Web.config</code>
+      file for ASP.NET:
+    </p>
+
+    <sample src="Web.config.ASPNetMaxRequestLength.bad" />
+
+    <p>
+      Unless such a high value is strictly needed, it is better to set
+      the recommended value (4096 KB):
+    </p>
+
+    <sample src="Web.config.ASPNetMaxRequestLength.good" />
+
+  </example>
+
+  <references>
+
+    <li>
+      MSDN:
+      <a href="https://docs.microsoft.com/en-us/dotnet/api/system.web.configuration.httpruntimesection.maxrequestlength?view=netframework-4.8">HttpRuntimeSection.MaxRequestLength Property</a>.
+    </li>
+  </references>
+</qhelp>

csharp/ql/src/Security Features/CWE-016/ASPNetMaxRequestLength.ql

@@ -0,0 +1,22 @@
+/**
+ * @name Large 'maxRequestLength' value
+ * @description Setting a large 'maxRequestLength' value may render a webpage vulnerable to
+ *              denial-of-service attacks.
+ * @kind problem
+ * @problem.severity warning
+ * @id cs/web/large-max-request-length
+ * @tags security
+ *       frameworks/asp.net
+ *       external/cwe/cwe-16
+ */
+
+import csharp
+import semmle.code.asp.WebConfig
+
+from SystemWebXMLElement web, XMLAttribute maxReqLength
+where
+  maxReqLength = web
+        .getAChild(any(string s | s.toLowerCase() = "httpruntime"))
+        .getAttribute(any(string s | s.toLowerCase() = "maxrequestlength")) and
+  maxReqLength.getValue().toInt() > 4096
+select maxReqLength, "Large 'maxRequestLength' value (" + maxReqLength.getValue() + " KB)."

csharp/ql/src/Security Features/CWE-016/Web.config.ASPNetMaxRequestLength.bad

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="utf-8" ?>
+<configuration>
+  <system.web>
+    <httpRuntime maxRequestLength="255000" />
+  </system.web>
+</configuration>

csharp/ql/src/Security Features/CWE-016/Web.config.ASPNetMaxRequestLength.good

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="utf-8" ?>
+<configuration>
+  <system.web>
+    <httpRuntime maxRequestLength="4096" />
+  </system.web>
+</configuration>

csharp/ql/src/semmle/code/csharp/dataflow/internal/DataFlowImpl.qll

@@ -464,7 +464,7 @@ private predicate simpleParameterFlow(
 ) {
   throughFlowNodeCand(node, config) and
   p = node and
-  t = getErasedRepr(node.getType()) and
+  t = getErasedNodeType(node) and
   exists(ReturnNode ret, ReturnKind kind |
     returnNodeGetEnclosingCallable(ret) = p.getEnclosingCallable() and
     kind = ret.getKind() and
@@ -475,21 +475,21 @@ private predicate simpleParameterFlow(
   exists(Node mid |
     simpleParameterFlow(p, mid, t, config) and
     localFlowStep(mid, node, config) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   throughFlowNodeCand(node, unbind(config)) and
   exists(Node mid |
     simpleParameterFlow(p, mid, _, config) and
     additionalLocalFlowStep(mid, node, config) and
-    t = getErasedRepr(node.getType())
+    t = getErasedNodeType(node)
   )
   or
   throughFlowNodeCand(node, unbind(config)) and
   exists(Node mid |
     simpleParameterFlow(p, mid, t, config) and
     localStoreReadStep(mid, node) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   // value flow through a callable
@@ -497,7 +497,7 @@ private predicate simpleParameterFlow(
   exists(Node arg |
     simpleParameterFlow(p, arg, t, config) and
     argumentValueFlowsThrough(arg, node, _) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   // flow through a callable
@@ -989,7 +989,9 @@ private class CastingNode extends Node {
  */
 private predicate flowCandFwd(Node node, boolean fromArg, AccessPathFront apf, Configuration config) {
   flowCandFwd0(node, fromArg, apf, config) and
-  if node instanceof CastingNode then compatibleTypes(node.getType(), apf.getType()) else any()
+  if node instanceof CastingNode
+  then compatibleTypes(getErasedNodeType(node), apf.getType())
+  else any()
 }
 
 /**
@@ -1010,7 +1012,7 @@ private class AccessPathFrontNilNode extends Node {
   }
 
   pragma[noinline]
-  private DataFlowType getErasedReprType() { result = getErasedRepr(this.getType()) }
+  private DataFlowType getErasedReprType() { result = getErasedNodeType(this) }
 
   /** Gets the `nil` path front for this node. */
   AccessPathFrontNil getApf() { result = TFrontNil(this.getErasedReprType()) }
@@ -1337,7 +1339,7 @@ private class AccessPathNilNode extends Node {
   AccessPathNilNode() { flowCand(this.(AccessPathFrontNilNode), _, _, _) }
 
   pragma[noinline]
-  private DataFlowType getErasedReprType() { result = getErasedRepr(this.getType()) }
+  private DataFlowType getErasedReprType() { result = getErasedNodeType(this) }
 
   /** Gets the `nil` path for this node. */
   AccessPathNil getAp() { result = TNil(this.getErasedReprType()) }
@@ -2076,7 +2078,7 @@ private module FlowExploration {
     TPartialPathNodeMk(Node node, CallContext cc, PartialAccessPath ap, Configuration config) {
       config.isSource(node) and
       cc instanceof CallContextAny and
-      ap = TPartialNil(getErasedRepr(node.getType())) and
+      ap = TPartialNil(getErasedNodeType(node)) and
       not fullBarrier(node, config) and
       exists(config.explorationLimit())
       or
@@ -2091,7 +2093,9 @@ private module FlowExploration {
     exists(PartialPathNode mid |
       partialPathStep(mid, node, cc, ap, config) and
       not fullBarrier(node, config) and
-      if node instanceof CastingNode then compatibleTypes(node.getType(), ap.getType()) else any()
+      if node instanceof CastingNode
+      then compatibleTypes(getErasedNodeType(node), ap.getType())
+      else any()
     )
   }
 
@@ -2194,7 +2198,7 @@ private module FlowExploration {
       additionalLocalFlowStep(mid.getNode(), node, config) and
       cc = mid.getCallContext() and
       mid.getAp() instanceof PartialAccessPathNil and
-      ap = TPartialNil(getErasedRepr(node.getType())) and
+      ap = TPartialNil(getErasedNodeType(node)) and
       config = mid.getConfiguration()
     )
     or
@@ -2206,7 +2210,7 @@ private module FlowExploration {
     additionalJumpStep(mid.getNode(), node, config) and
     cc instanceof CallContextAny and
     mid.getAp() instanceof PartialAccessPathNil and
-    ap = TPartialNil(getErasedRepr(node.getType())) and
+    ap = TPartialNil(getErasedNodeType(node)) and
     config = mid.getConfiguration()
     or
     partialPathStoreStep(mid, _, _, node, ap) and

csharp/ql/src/semmle/code/csharp/dataflow/internal/DataFlowImpl2.qll

@@ -464,7 +464,7 @@ private predicate simpleParameterFlow(
 ) {
   throughFlowNodeCand(node, config) and
   p = node and
-  t = getErasedRepr(node.getType()) and
+  t = getErasedNodeType(node) and
   exists(ReturnNode ret, ReturnKind kind |
     returnNodeGetEnclosingCallable(ret) = p.getEnclosingCallable() and
     kind = ret.getKind() and
@@ -475,21 +475,21 @@ private predicate simpleParameterFlow(
   exists(Node mid |
     simpleParameterFlow(p, mid, t, config) and
     localFlowStep(mid, node, config) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   throughFlowNodeCand(node, unbind(config)) and
   exists(Node mid |
     simpleParameterFlow(p, mid, _, config) and
     additionalLocalFlowStep(mid, node, config) and
-    t = getErasedRepr(node.getType())
+    t = getErasedNodeType(node)
   )
   or
   throughFlowNodeCand(node, unbind(config)) and
   exists(Node mid |
     simpleParameterFlow(p, mid, t, config) and
     localStoreReadStep(mid, node) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   // value flow through a callable
@@ -497,7 +497,7 @@ private predicate simpleParameterFlow(
   exists(Node arg |
     simpleParameterFlow(p, arg, t, config) and
     argumentValueFlowsThrough(arg, node, _) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   // flow through a callable
@@ -989,7 +989,9 @@ private class CastingNode extends Node {
  */
 private predicate flowCandFwd(Node node, boolean fromArg, AccessPathFront apf, Configuration config) {
   flowCandFwd0(node, fromArg, apf, config) and
-  if node instanceof CastingNode then compatibleTypes(node.getType(), apf.getType()) else any()
+  if node instanceof CastingNode
+  then compatibleTypes(getErasedNodeType(node), apf.getType())
+  else any()
 }
 
 /**
@@ -1010,7 +1012,7 @@ private class AccessPathFrontNilNode extends Node {
   }
 
   pragma[noinline]
-  private DataFlowType getErasedReprType() { result = getErasedRepr(this.getType()) }
+  private DataFlowType getErasedReprType() { result = getErasedNodeType(this) }
 
   /** Gets the `nil` path front for this node. */
   AccessPathFrontNil getApf() { result = TFrontNil(this.getErasedReprType()) }
@@ -1337,7 +1339,7 @@ private class AccessPathNilNode extends Node {
   AccessPathNilNode() { flowCand(this.(AccessPathFrontNilNode), _, _, _) }
 
   pragma[noinline]
-  private DataFlowType getErasedReprType() { result = getErasedRepr(this.getType()) }
+  private DataFlowType getErasedReprType() { result = getErasedNodeType(this) }
 
   /** Gets the `nil` path for this node. */
   AccessPathNil getAp() { result = TNil(this.getErasedReprType()) }
@@ -2076,7 +2078,7 @@ private module FlowExploration {
     TPartialPathNodeMk(Node node, CallContext cc, PartialAccessPath ap, Configuration config) {
       config.isSource(node) and
       cc instanceof CallContextAny and
-      ap = TPartialNil(getErasedRepr(node.getType())) and
+      ap = TPartialNil(getErasedNodeType(node)) and
       not fullBarrier(node, config) and
       exists(config.explorationLimit())
       or
@@ -2091,7 +2093,9 @@ private module FlowExploration {
     exists(PartialPathNode mid |
       partialPathStep(mid, node, cc, ap, config) and
       not fullBarrier(node, config) and
-      if node instanceof CastingNode then compatibleTypes(node.getType(), ap.getType()) else any()
+      if node instanceof CastingNode
+      then compatibleTypes(getErasedNodeType(node), ap.getType())
+      else any()
     )
   }
 
@@ -2194,7 +2198,7 @@ private module FlowExploration {
       additionalLocalFlowStep(mid.getNode(), node, config) and
       cc = mid.getCallContext() and
       mid.getAp() instanceof PartialAccessPathNil and
-      ap = TPartialNil(getErasedRepr(node.getType())) and
+      ap = TPartialNil(getErasedNodeType(node)) and
       config = mid.getConfiguration()
     )
     or
@@ -2206,7 +2210,7 @@ private module FlowExploration {
     additionalJumpStep(mid.getNode(), node, config) and
     cc instanceof CallContextAny and
     mid.getAp() instanceof PartialAccessPathNil and
-    ap = TPartialNil(getErasedRepr(node.getType())) and
+    ap = TPartialNil(getErasedNodeType(node)) and
     config = mid.getConfiguration()
     or
     partialPathStoreStep(mid, _, _, node, ap) and

csharp/ql/src/semmle/code/csharp/dataflow/internal/DataFlowImpl3.qll

@@ -464,7 +464,7 @@ private predicate simpleParameterFlow(
 ) {
   throughFlowNodeCand(node, config) and
   p = node and
-  t = getErasedRepr(node.getType()) and
+  t = getErasedNodeType(node) and
   exists(ReturnNode ret, ReturnKind kind |
     returnNodeGetEnclosingCallable(ret) = p.getEnclosingCallable() and
     kind = ret.getKind() and
@@ -475,21 +475,21 @@ private predicate simpleParameterFlow(
   exists(Node mid |
     simpleParameterFlow(p, mid, t, config) and
     localFlowStep(mid, node, config) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   throughFlowNodeCand(node, unbind(config)) and
   exists(Node mid |
     simpleParameterFlow(p, mid, _, config) and
     additionalLocalFlowStep(mid, node, config) and
-    t = getErasedRepr(node.getType())
+    t = getErasedNodeType(node)
   )
   or
   throughFlowNodeCand(node, unbind(config)) and
   exists(Node mid |
     simpleParameterFlow(p, mid, t, config) and
     localStoreReadStep(mid, node) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   // value flow through a callable
@@ -497,7 +497,7 @@ private predicate simpleParameterFlow(
   exists(Node arg |
     simpleParameterFlow(p, arg, t, config) and
     argumentValueFlowsThrough(arg, node, _) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   // flow through a callable
@@ -989,7 +989,9 @@ private class CastingNode extends Node {
  */
 private predicate flowCandFwd(Node node, boolean fromArg, AccessPathFront apf, Configuration config) {
   flowCandFwd0(node, fromArg, apf, config) and
-  if node instanceof CastingNode then compatibleTypes(node.getType(), apf.getType()) else any()
+  if node instanceof CastingNode
+  then compatibleTypes(getErasedNodeType(node), apf.getType())
+  else any()
 }
 
 /**
@@ -1010,7 +1012,7 @@ private class AccessPathFrontNilNode extends Node {
   }
 
   pragma[noinline]
-  private DataFlowType getErasedReprType() { result = getErasedRepr(this.getType()) }
+  private DataFlowType getErasedReprType() { result = getErasedNodeType(this) }
 
   /** Gets the `nil` path front for this node. */
   AccessPathFrontNil getApf() { result = TFrontNil(this.getErasedReprType()) }
@@ -1337,7 +1339,7 @@ private class AccessPathNilNode extends Node {
   AccessPathNilNode() { flowCand(this.(AccessPathFrontNilNode), _, _, _) }
 
   pragma[noinline]
-  private DataFlowType getErasedReprType() { result = getErasedRepr(this.getType()) }
+  private DataFlowType getErasedReprType() { result = getErasedNodeType(this) }
 
   /** Gets the `nil` path for this node. */
   AccessPathNil getAp() { result = TNil(this.getErasedReprType()) }
@@ -2076,7 +2078,7 @@ private module FlowExploration {
     TPartialPathNodeMk(Node node, CallContext cc, PartialAccessPath ap, Configuration config) {
       config.isSource(node) and
       cc instanceof CallContextAny and
-      ap = TPartialNil(getErasedRepr(node.getType())) and
+      ap = TPartialNil(getErasedNodeType(node)) and
       not fullBarrier(node, config) and
       exists(config.explorationLimit())
       or
@@ -2091,7 +2093,9 @@ private module FlowExploration {
     exists(PartialPathNode mid |
       partialPathStep(mid, node, cc, ap, config) and
       not fullBarrier(node, config) and
-      if node instanceof CastingNode then compatibleTypes(node.getType(), ap.getType()) else any()
+      if node instanceof CastingNode
+      then compatibleTypes(getErasedNodeType(node), ap.getType())
+      else any()
     )
   }
 
@@ -2194,7 +2198,7 @@ private module FlowExploration {
       additionalLocalFlowStep(mid.getNode(), node, config) and
       cc = mid.getCallContext() and
       mid.getAp() instanceof PartialAccessPathNil and
-      ap = TPartialNil(getErasedRepr(node.getType())) and
+      ap = TPartialNil(getErasedNodeType(node)) and
       config = mid.getConfiguration()
     )
     or
@@ -2206,7 +2210,7 @@ private module FlowExploration {
     additionalJumpStep(mid.getNode(), node, config) and
     cc instanceof CallContextAny and
     mid.getAp() instanceof PartialAccessPathNil and
-    ap = TPartialNil(getErasedRepr(node.getType())) and
+    ap = TPartialNil(getErasedNodeType(node)) and
     config = mid.getConfiguration()
     or
     partialPathStoreStep(mid, _, _, node, ap) and

csharp/ql/src/semmle/code/csharp/dataflow/internal/DataFlowImpl4.qll

@@ -464,7 +464,7 @@ private predicate simpleParameterFlow(
 ) {
   throughFlowNodeCand(node, config) and
   p = node and
-  t = getErasedRepr(node.getType()) and
+  t = getErasedNodeType(node) and
   exists(ReturnNode ret, ReturnKind kind |
     returnNodeGetEnclosingCallable(ret) = p.getEnclosingCallable() and
     kind = ret.getKind() and
@@ -475,21 +475,21 @@ private predicate simpleParameterFlow(
   exists(Node mid |
     simpleParameterFlow(p, mid, t, config) and
     localFlowStep(mid, node, config) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   throughFlowNodeCand(node, unbind(config)) and
   exists(Node mid |
     simpleParameterFlow(p, mid, _, config) and
     additionalLocalFlowStep(mid, node, config) and
-    t = getErasedRepr(node.getType())
+    t = getErasedNodeType(node)
   )
   or
   throughFlowNodeCand(node, unbind(config)) and
   exists(Node mid |
     simpleParameterFlow(p, mid, t, config) and
     localStoreReadStep(mid, node) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   // value flow through a callable
@@ -497,7 +497,7 @@ private predicate simpleParameterFlow(
   exists(Node arg |
     simpleParameterFlow(p, arg, t, config) and
     argumentValueFlowsThrough(arg, node, _) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   // flow through a callable
@@ -989,7 +989,9 @@ private class CastingNode extends Node {
  */
 private predicate flowCandFwd(Node node, boolean fromArg, AccessPathFront apf, Configuration config) {
   flowCandFwd0(node, fromArg, apf, config) and
-  if node instanceof CastingNode then compatibleTypes(node.getType(), apf.getType()) else any()
+  if node instanceof CastingNode
+  then compatibleTypes(getErasedNodeType(node), apf.getType())
+  else any()
 }
 
 /**
@@ -1010,7 +1012,7 @@ private class AccessPathFrontNilNode extends Node {
   }
 
   pragma[noinline]
-  private DataFlowType getErasedReprType() { result = getErasedRepr(this.getType()) }
+  private DataFlowType getErasedReprType() { result = getErasedNodeType(this) }
 
   /** Gets the `nil` path front for this node. */
   AccessPathFrontNil getApf() { result = TFrontNil(this.getErasedReprType()) }
@@ -1337,7 +1339,7 @@ private class AccessPathNilNode extends Node {
   AccessPathNilNode() { flowCand(this.(AccessPathFrontNilNode), _, _, _) }
 
   pragma[noinline]
-  private DataFlowType getErasedReprType() { result = getErasedRepr(this.getType()) }
+  private DataFlowType getErasedReprType() { result = getErasedNodeType(this) }
 
   /** Gets the `nil` path for this node. */
   AccessPathNil getAp() { result = TNil(this.getErasedReprType()) }
@@ -2076,7 +2078,7 @@ private module FlowExploration {
     TPartialPathNodeMk(Node node, CallContext cc, PartialAccessPath ap, Configuration config) {
       config.isSource(node) and
       cc instanceof CallContextAny and
-      ap = TPartialNil(getErasedRepr(node.getType())) and
+      ap = TPartialNil(getErasedNodeType(node)) and
       not fullBarrier(node, config) and
       exists(config.explorationLimit())
       or
@@ -2091,7 +2093,9 @@ private module FlowExploration {
     exists(PartialPathNode mid |
       partialPathStep(mid, node, cc, ap, config) and
       not fullBarrier(node, config) and
-      if node instanceof CastingNode then compatibleTypes(node.getType(), ap.getType()) else any()
+      if node instanceof CastingNode
+      then compatibleTypes(getErasedNodeType(node), ap.getType())
+      else any()
     )
   }
 
@@ -2194,7 +2198,7 @@ private module FlowExploration {
       additionalLocalFlowStep(mid.getNode(), node, config) and
       cc = mid.getCallContext() and
       mid.getAp() instanceof PartialAccessPathNil and
-      ap = TPartialNil(getErasedRepr(node.getType())) and
+      ap = TPartialNil(getErasedNodeType(node)) and
       config = mid.getConfiguration()
     )
     or
@@ -2206,7 +2210,7 @@ private module FlowExploration {
     additionalJumpStep(mid.getNode(), node, config) and
     cc instanceof CallContextAny and
     mid.getAp() instanceof PartialAccessPathNil and
-    ap = TPartialNil(getErasedRepr(node.getType())) and
+    ap = TPartialNil(getErasedNodeType(node)) and
     config = mid.getConfiguration()
     or
     partialPathStoreStep(mid, _, _, node, ap) and

csharp/ql/src/semmle/code/csharp/dataflow/internal/DataFlowImpl5.qll

@@ -464,7 +464,7 @@ private predicate simpleParameterFlow(
 ) {
   throughFlowNodeCand(node, config) and
   p = node and
-  t = getErasedRepr(node.getType()) and
+  t = getErasedNodeType(node) and
   exists(ReturnNode ret, ReturnKind kind |
     returnNodeGetEnclosingCallable(ret) = p.getEnclosingCallable() and
     kind = ret.getKind() and
@@ -475,21 +475,21 @@ private predicate simpleParameterFlow(
   exists(Node mid |
     simpleParameterFlow(p, mid, t, config) and
     localFlowStep(mid, node, config) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   throughFlowNodeCand(node, unbind(config)) and
   exists(Node mid |
     simpleParameterFlow(p, mid, _, config) and
     additionalLocalFlowStep(mid, node, config) and
-    t = getErasedRepr(node.getType())
+    t = getErasedNodeType(node)
   )
   or
   throughFlowNodeCand(node, unbind(config)) and
   exists(Node mid |
     simpleParameterFlow(p, mid, t, config) and
     localStoreReadStep(mid, node) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   // value flow through a callable
@@ -497,7 +497,7 @@ private predicate simpleParameterFlow(
   exists(Node arg |
     simpleParameterFlow(p, arg, t, config) and
     argumentValueFlowsThrough(arg, node, _) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   // flow through a callable
@@ -989,7 +989,9 @@ private class CastingNode extends Node {
  */
 private predicate flowCandFwd(Node node, boolean fromArg, AccessPathFront apf, Configuration config) {
   flowCandFwd0(node, fromArg, apf, config) and
-  if node instanceof CastingNode then compatibleTypes(node.getType(), apf.getType()) else any()
+  if node instanceof CastingNode
+  then compatibleTypes(getErasedNodeType(node), apf.getType())
+  else any()
 }
 
 /**
@@ -1010,7 +1012,7 @@ private class AccessPathFrontNilNode extends Node {
   }
 
   pragma[noinline]
-  private DataFlowType getErasedReprType() { result = getErasedRepr(this.getType()) }
+  private DataFlowType getErasedReprType() { result = getErasedNodeType(this) }
 
   /** Gets the `nil` path front for this node. */
   AccessPathFrontNil getApf() { result = TFrontNil(this.getErasedReprType()) }
@@ -1337,7 +1339,7 @@ private class AccessPathNilNode extends Node {
   AccessPathNilNode() { flowCand(this.(AccessPathFrontNilNode), _, _, _) }
 
   pragma[noinline]
-  private DataFlowType getErasedReprType() { result = getErasedRepr(this.getType()) }
+  private DataFlowType getErasedReprType() { result = getErasedNodeType(this) }
 
   /** Gets the `nil` path for this node. */
   AccessPathNil getAp() { result = TNil(this.getErasedReprType()) }
@@ -2076,7 +2078,7 @@ private module FlowExploration {
     TPartialPathNodeMk(Node node, CallContext cc, PartialAccessPath ap, Configuration config) {
       config.isSource(node) and
       cc instanceof CallContextAny and
-      ap = TPartialNil(getErasedRepr(node.getType())) and
+      ap = TPartialNil(getErasedNodeType(node)) and
       not fullBarrier(node, config) and
       exists(config.explorationLimit())
       or
@@ -2091,7 +2093,9 @@ private module FlowExploration {
     exists(PartialPathNode mid |
       partialPathStep(mid, node, cc, ap, config) and
       not fullBarrier(node, config) and
-      if node instanceof CastingNode then compatibleTypes(node.getType(), ap.getType()) else any()
+      if node instanceof CastingNode
+      then compatibleTypes(getErasedNodeType(node), ap.getType())
+      else any()
     )
   }
 
@@ -2194,7 +2198,7 @@ private module FlowExploration {
       additionalLocalFlowStep(mid.getNode(), node, config) and
       cc = mid.getCallContext() and
       mid.getAp() instanceof PartialAccessPathNil and
-      ap = TPartialNil(getErasedRepr(node.getType())) and
+      ap = TPartialNil(getErasedNodeType(node)) and
       config = mid.getConfiguration()
     )
     or
@@ -2206,7 +2210,7 @@ private module FlowExploration {
     additionalJumpStep(mid.getNode(), node, config) and
     cc instanceof CallContextAny and
     mid.getAp() instanceof PartialAccessPathNil and
-    ap = TPartialNil(getErasedRepr(node.getType())) and
+    ap = TPartialNil(getErasedNodeType(node)) and
     config = mid.getConfiguration()
     or
     partialPathStoreStep(mid, _, _, node, ap) and

csharp/ql/src/semmle/code/csharp/dataflow/internal/DataFlowImplCommon.qll

@@ -57,14 +57,14 @@ private module ImplCommon {
         exists(Node mid |
           parameterValueFlowCand(p, mid) and
           step(mid, node) and
-          compatibleTypes(p.getType(), node.getType())
+          compatibleTypes(getErasedNodeType(p), getErasedNodeType(node))
         )
         or
         // flow through a callable
         exists(Node arg |
           parameterValueFlowCand(p, arg) and
           argumentValueFlowsThroughCand(arg, node) and
-          compatibleTypes(p.getType(), node.getType())
+          compatibleTypes(getErasedNodeType(p), getErasedNodeType(node))
         )
       }
 
@@ -95,7 +95,7 @@ private module ImplCommon {
           argumentValueFlowsThroughCand0(call, arg, kind)
         |
           out = getAnOutNode(call, kind) and
-          compatibleTypes(arg.getType(), out.getType())
+          compatibleTypes(getErasedNodeType(arg), getErasedNodeType(out))
         )
       }
 
@@ -183,7 +183,7 @@ private module ImplCommon {
         exists(Node mid |
           parameterValueFlow(p, mid, cc) and
           step(mid, node) and
-          compatibleTypes(p.getType(), node.getType()) and
+          compatibleTypes(getErasedNodeType(p), getErasedNodeType(node)) and
           not isUnreachableInCall(node, cc.(CallContextSpecificCall).getCall())
         )
         or
@@ -191,7 +191,7 @@ private module ImplCommon {
         exists(Node arg |
           parameterValueFlow(p, arg, cc) and
           argumentValueFlowsThrough(arg, node, cc) and
-          compatibleTypes(p.getType(), node.getType()) and
+          compatibleTypes(getErasedNodeType(p), getErasedNodeType(node)) and
           not isUnreachableInCall(node, cc.(CallContextSpecificCall).getCall())
         )
       }
@@ -226,7 +226,7 @@ private module ImplCommon {
         |
           out = getAnOutNode(call, kind) and
           not isUnreachableInCall(out, cc.(CallContextSpecificCall).getCall()) and
-          compatibleTypes(arg.getType(), out.getType())
+          compatibleTypes(getErasedNodeType(arg), getErasedNodeType(out))
         )
       }
     }
@@ -260,7 +260,7 @@ private module ImplCommon {
       exists(Node mid |
         parameterValueFlowNoCtx(p, mid) and
         localValueStep(mid, node) and
-        compatibleTypes(p.getType(), node.getType())
+        compatibleTypes(getErasedNodeType(p), getErasedNodeType(node))
       )
     }
 
@@ -296,8 +296,8 @@ private module ImplCommon {
         setterCall(call, i1, i2, f) and
         node1.(ArgumentNode).argumentOf(call, i1) and
         node2.getPreUpdateNode().(ArgumentNode).argumentOf(call, i2) and
-        compatibleTypes(node1.getTypeBound(), f.getType()) and
-        compatibleTypes(node2.getTypeBound(), f.getContainerType())
+        compatibleTypes(getErasedNodeTypeBound(node1), f.getType()) and
+        compatibleTypes(getErasedNodeTypeBound(node2), f.getContainerType())
       )
     }
 
@@ -333,8 +333,8 @@ private module ImplCommon {
       exists(DataFlowCall call, ReturnKind kind |
         storeReturn0(call, kind, node1, f) and
         node2 = getAnOutNode(call, kind) and
-        compatibleTypes(node1.getTypeBound(), f.getType()) and
-        compatibleTypes(node2.getTypeBound(), f.getContainerType())
+        compatibleTypes(getErasedNodeTypeBound(node1), f.getType()) and
+        compatibleTypes(getErasedNodeTypeBound(node2), f.getContainerType())
       )
     }
 
@@ -365,8 +365,8 @@ private module ImplCommon {
       exists(DataFlowCall call, ReturnKind kind |
         read0(call, kind, node1, f) and
         node2 = getAnOutNode(call, kind) and
-        compatibleTypes(node1.getTypeBound(), f.getContainerType()) and
-        compatibleTypes(node2.getTypeBound(), f.getType())
+        compatibleTypes(getErasedNodeTypeBound(node1), f.getContainerType()) and
+        compatibleTypes(getErasedNodeTypeBound(node2), f.getType())
       )
     }
 
@@ -384,7 +384,7 @@ private module ImplCommon {
         store(node1, f, mid1) and
         localValueStep*(mid1, mid2) and
         read(mid2, f, node2) and
-        compatibleTypes(node1.getTypeBound(), node2.getTypeBound())
+        compatibleTypes(getErasedNodeTypeBound(node1), getErasedNodeTypeBound(node2))
       )
     }
 
@@ -405,14 +405,14 @@ private module ImplCommon {
         exists(Node mid |
           parameterValueFlowCand(p, mid) and
           step(mid, node) and
-          compatibleTypes(p.getType(), node.getType())
+          compatibleTypes(getErasedNodeType(p), getErasedNodeType(node))
         )
         or
         // flow through a callable
         exists(Node arg |
           parameterValueFlowCand(p, arg) and
           argumentValueFlowsThroughCand(arg, node) and
-          compatibleTypes(p.getType(), node.getType())
+          compatibleTypes(getErasedNodeType(p), getErasedNodeType(node))
         )
       }
 
@@ -443,7 +443,7 @@ private module ImplCommon {
           argumentValueFlowsThroughCand0(call, arg, kind)
         |
           out = getAnOutNode(call, kind) and
-          compatibleTypes(arg.getType(), out.getType())
+          compatibleTypes(getErasedNodeType(arg), getErasedNodeType(out))
         )
       }
 
@@ -531,7 +531,7 @@ private module ImplCommon {
         exists(Node mid |
           parameterValueFlow(p, mid, cc) and
           step(mid, node) and
-          compatibleTypes(p.getType(), node.getType()) and
+          compatibleTypes(getErasedNodeType(p), getErasedNodeType(node)) and
           not isUnreachableInCall(node, cc.(CallContextSpecificCall).getCall())
         )
         or
@@ -539,7 +539,7 @@ private module ImplCommon {
         exists(Node arg |
           parameterValueFlow(p, arg, cc) and
           argumentValueFlowsThrough(arg, node, cc) and
-          compatibleTypes(p.getType(), node.getType()) and
+          compatibleTypes(getErasedNodeType(p), getErasedNodeType(node)) and
           not isUnreachableInCall(node, cc.(CallContextSpecificCall).getCall())
         )
       }
@@ -574,7 +574,7 @@ private module ImplCommon {
         |
           out = getAnOutNode(call, kind) and
           not isUnreachableInCall(out, cc.(CallContextSpecificCall).getCall()) and
-          compatibleTypes(arg.getType(), out.getType())
+          compatibleTypes(getErasedNodeType(arg), getErasedNodeType(out))
         )
       }
     }
@@ -860,4 +860,10 @@ private module ImplCommon {
     or
     result = viableCallable(call) and cc instanceof CallContextReturn
   }
+
+  pragma[noinline]
+  DataFlowType getErasedNodeType(Node n) { result = getErasedRepr(n.getType()) }
+
+  pragma[noinline]
+  DataFlowType getErasedNodeTypeBound(Node n) { result = getErasedRepr(n.getTypeBound()) }
 }

csharp/ql/src/semmle/code/csharp/dataflow/internal/DataFlowPrivate.qll

@@ -1307,7 +1307,7 @@ private predicate suppressUnusedType(DotNet::Type t) { any() }
  * Type-based pruning is disabled for now, so this is a stub implementation.
  */
 bindingset[t]
-DotNet::Type getErasedRepr(DotNet::Type t) {
+DataFlowType getErasedRepr(DotNet::Type t) {
   // stub implementation
   suppressUnusedType(t) and result instanceof ObjectType
 }

csharp/ql/src/semmle/code/csharp/ir/implementation/raw/IRVariable.qll

@@ -13,14 +13,20 @@ IRUserVariable getIRUserVariable(Language::Function func, Language::Variable var
 }
 
 /**
- * Represents a variable referenced by the IR for a function. The variable may
- * be a user-declared variable (`IRUserVariable`) or a temporary variable
- * generated by the AST-to-IR translation (`IRTempVariable`).
+ * A variable referenced by the IR for a function. The variable may be a user-declared variable
+ * (`IRUserVariable`) or a temporary variable generated by the AST-to-IR translation
+ * (`IRTempVariable`).
  */
-abstract class IRVariable extends TIRVariable {
+class IRVariable extends TIRVariable {
   Language::Function func;
 
-  abstract string toString();
+  IRVariable() {
+    this = TIRUserVariable(_, _, func) or
+    this = TIRTempVariable(func, _, _, _) or
+    this = TIRStringLiteral(func, _, _, _)
+  }
+
+  string toString() { none() }
 
   /**
    * Holds if this variable's value cannot be changed within a function. Currently used for string
@@ -41,19 +47,19 @@ abstract class IRVariable extends TIRVariable {
   /**
    * Gets the type of the variable.
    */
-  abstract Language::LanguageType getLanguageType();
+  Language::LanguageType getLanguageType() { none() }
 
   /**
    * Gets the AST node that declared this variable, or that introduced this
    * variable as part of the AST-to-IR translation.
    */
-  abstract Language::AST getAST();
+  Language::AST getAST() { none() }
 
   /**
    * Gets an identifier string for the variable. This identifier is unique
    * within the function.
    */
-  abstract string getUniqueId();
+  string getUniqueId() { none() }
 
   /**
    * Gets the source location of this variable.
@@ -72,7 +78,7 @@ abstract class IRVariable extends TIRVariable {
 }
 
 /**
- * Represents a user-declared variable referenced by the IR for a function.
+ * A user-declared variable referenced by the IR for a function.
  */
 class IRUserVariable extends IRVariable, TIRUserVariable {
   Language::Variable var;
@@ -97,20 +103,34 @@ class IRUserVariable extends IRVariable, TIRUserVariable {
 }
 
 /**
- * Represents a variable (user-declared or temporary) that is allocated on the
- * stack. This includes all parameters, non-static local variables, and
- * temporary variables.
+ * A variable (user-declared or temporary) that is allocated on the stack. This includes all
+ * parameters, non-static local variables, and temporary variables.
  */
-abstract class IRAutomaticVariable extends IRVariable { }
+class IRAutomaticVariable extends IRVariable {
+  IRAutomaticVariable() {
+    exists(Language::Variable var |
+      this = TIRUserVariable(var, _, func) and
+      Language::isVariableAutomatic(var)
+    )
+    or
+    this = TIRTempVariable(func, _, _, _)
+  }
+}
 
+/**
+ * A user-declared variable that is allocated on the stack. This includes all parameters and
+ * non-static local variables.
+ */
 class IRAutomaticUserVariable extends IRUserVariable, IRAutomaticVariable {
   override Language::AutomaticVariable var;
 
-  IRAutomaticUserVariable() { Language::isVariableAutomatic(var) }
-
   final override Language::AutomaticVariable getVariable() { result = var }
 }
 
+/**
+ * A user-declared variable that is not allocated on the stack. This includes all global variables,
+ * namespace-scope variables, static fields, and static local variables.
+ */
 class IRStaticUserVariable extends IRUserVariable {
   override Language::StaticVariable var;
 
@@ -119,10 +139,19 @@ class IRStaticUserVariable extends IRUserVariable {
   final override Language::StaticVariable getVariable() { result = var }
 }
 
-abstract class IRGeneratedVariable extends IRVariable {
+/**
+ * A variable that is not user-declared. This includes temporary variables generated as part of IR
+ * construction, as well as string literals.
+ */
+class IRGeneratedVariable extends IRVariable {
   Language::AST ast;
   Language::LanguageType type;
 
+  IRGeneratedVariable() {
+    this = TIRTempVariable(func, ast, _, type) or
+    this = TIRStringLiteral(func, ast, type, _)
+  }
+
   final override Language::LanguageType getLanguageType() { result = type }
 
   final override Language::AST getAST() { result = ast }
@@ -144,6 +173,11 @@ IRTempVariable getIRTempVariable(Language::AST ast, TempVariableTag tag) {
   result.getTag() = tag
 }
 
+/**
+ * A temporary variable introduced by IR construction. The most common examples are the variable
+ * generated to hold the return value of afunction, or the variable generated to hold the result of
+ * a condition operator (`a ? b : c`).
+ */
 class IRTempVariable extends IRGeneratedVariable, IRAutomaticVariable, TIRTempVariable {
   TempVariableTag tag;
 
@@ -158,18 +192,28 @@ class IRTempVariable extends IRGeneratedVariable, IRAutomaticVariable, TIRTempVa
   override string getBaseString() { result = "#temp" }
 }
 
+/**
+ * A temporary variable generated to hold the return value of a function.
+ */
 class IRReturnVariable extends IRTempVariable {
   IRReturnVariable() { tag = ReturnValueTempVar() }
 
   final override string toString() { result = "#return" }
 }
 
+/**
+ * A temporary variable generated to hold the exception thrown by a `ThrowValue` instruction.
+ */
 class IRThrowVariable extends IRTempVariable {
   IRThrowVariable() { tag = ThrowTempVar() }
 
   override string getBaseString() { result = "#throw" }
 }
 
+/**
+ * A variable generated to represent the contents of a string literal. This variable acts much like
+ * a read-only global variable.
+ */
 class IRStringLiteral extends IRGeneratedVariable, TIRStringLiteral {
   Language::StringLiteral literal;
 

csharp/ql/src/semmle/code/csharp/ir/implementation/raw/Instruction.qll

@@ -94,12 +94,21 @@ module InstructionSanity {
   /**
    * Holds if instruction `instr` has multiple operands with tag `tag`.
    */
-  query predicate duplicateOperand(Instruction instr, OperandTag tag) {
-    strictcount(NonPhiOperand operand |
-      operand = instr.getAnOperand() and
-      operand.getOperandTag() = tag
-    ) > 1 and
-    not tag instanceof UnmodeledUseOperandTag
+  query predicate duplicateOperand(
+    Instruction instr, string message, IRFunction func, string funcText
+  ) {
+    exists(OperandTag tag, int operandCount |
+      operandCount = strictcount(NonPhiOperand operand |
+          operand = instr.getAnOperand() and
+          operand.getOperandTag() = tag
+        ) and
+      operandCount > 1 and
+      not tag instanceof UnmodeledUseOperandTag and
+      message = "Instruction has " + operandCount + " operands with tag '" + tag.toString() + "'" +
+          " in function '$@'." and
+      func = instr.getEnclosingIRFunction() and
+      funcText = Language::getIdentityString(func.getFunction())
+    )
   }
 
   /**

csharp/ql/src/semmle/code/csharp/ir/implementation/unaliased_ssa/IRVariable.qll

@@ -13,14 +13,20 @@ IRUserVariable getIRUserVariable(Language::Function func, Language::Variable var
 }
 
 /**
- * Represents a variable referenced by the IR for a function. The variable may
- * be a user-declared variable (`IRUserVariable`) or a temporary variable
- * generated by the AST-to-IR translation (`IRTempVariable`).
+ * A variable referenced by the IR for a function. The variable may be a user-declared variable
+ * (`IRUserVariable`) or a temporary variable generated by the AST-to-IR translation
+ * (`IRTempVariable`).
  */
-abstract class IRVariable extends TIRVariable {
+class IRVariable extends TIRVariable {
   Language::Function func;
 
-  abstract string toString();
+  IRVariable() {
+    this = TIRUserVariable(_, _, func) or
+    this = TIRTempVariable(func, _, _, _) or
+    this = TIRStringLiteral(func, _, _, _)
+  }
+
+  string toString() { none() }
 
   /**
    * Holds if this variable's value cannot be changed within a function. Currently used for string
@@ -41,19 +47,19 @@ abstract class IRVariable extends TIRVariable {
   /**
    * Gets the type of the variable.
    */
-  abstract Language::LanguageType getLanguageType();
+  Language::LanguageType getLanguageType() { none() }
 
   /**
    * Gets the AST node that declared this variable, or that introduced this
    * variable as part of the AST-to-IR translation.
    */
-  abstract Language::AST getAST();
+  Language::AST getAST() { none() }
 
   /**
    * Gets an identifier string for the variable. This identifier is unique
    * within the function.
    */
-  abstract string getUniqueId();
+  string getUniqueId() { none() }
 
   /**
    * Gets the source location of this variable.
@@ -72,7 +78,7 @@ abstract class IRVariable extends TIRVariable {
 }
 
 /**
- * Represents a user-declared variable referenced by the IR for a function.
+ * A user-declared variable referenced by the IR for a function.
  */
 class IRUserVariable extends IRVariable, TIRUserVariable {
   Language::Variable var;
@@ -97,20 +103,34 @@ class IRUserVariable extends IRVariable, TIRUserVariable {
 }
 
 /**
- * Represents a variable (user-declared or temporary) that is allocated on the
- * stack. This includes all parameters, non-static local variables, and
- * temporary variables.
+ * A variable (user-declared or temporary) that is allocated on the stack. This includes all
+ * parameters, non-static local variables, and temporary variables.
  */
-abstract class IRAutomaticVariable extends IRVariable { }
+class IRAutomaticVariable extends IRVariable {
+  IRAutomaticVariable() {
+    exists(Language::Variable var |
+      this = TIRUserVariable(var, _, func) and
+      Language::isVariableAutomatic(var)
+    )
+    or
+    this = TIRTempVariable(func, _, _, _)
+  }
+}
 
+/**
+ * A user-declared variable that is allocated on the stack. This includes all parameters and
+ * non-static local variables.
+ */
 class IRAutomaticUserVariable extends IRUserVariable, IRAutomaticVariable {
   override Language::AutomaticVariable var;
 
-  IRAutomaticUserVariable() { Language::isVariableAutomatic(var) }
-
   final override Language::AutomaticVariable getVariable() { result = var }
 }
 
+/**
+ * A user-declared variable that is not allocated on the stack. This includes all global variables,
+ * namespace-scope variables, static fields, and static local variables.
+ */
 class IRStaticUserVariable extends IRUserVariable {
   override Language::StaticVariable var;
 
@@ -119,10 +139,19 @@ class IRStaticUserVariable extends IRUserVariable {
   final override Language::StaticVariable getVariable() { result = var }
 }
 
-abstract class IRGeneratedVariable extends IRVariable {
+/**
+ * A variable that is not user-declared. This includes temporary variables generated as part of IR
+ * construction, as well as string literals.
+ */
+class IRGeneratedVariable extends IRVariable {
   Language::AST ast;
   Language::LanguageType type;
 
+  IRGeneratedVariable() {
+    this = TIRTempVariable(func, ast, _, type) or
+    this = TIRStringLiteral(func, ast, type, _)
+  }
+
   final override Language::LanguageType getLanguageType() { result = type }
 
   final override Language::AST getAST() { result = ast }
@@ -144,6 +173,11 @@ IRTempVariable getIRTempVariable(Language::AST ast, TempVariableTag tag) {
   result.getTag() = tag
 }
 
+/**
+ * A temporary variable introduced by IR construction. The most common examples are the variable
+ * generated to hold the return value of afunction, or the variable generated to hold the result of
+ * a condition operator (`a ? b : c`).
+ */
 class IRTempVariable extends IRGeneratedVariable, IRAutomaticVariable, TIRTempVariable {
   TempVariableTag tag;
 
@@ -158,18 +192,28 @@ class IRTempVariable extends IRGeneratedVariable, IRAutomaticVariable, TIRTempVa
   override string getBaseString() { result = "#temp" }
 }
 
+/**
+ * A temporary variable generated to hold the return value of a function.
+ */
 class IRReturnVariable extends IRTempVariable {
   IRReturnVariable() { tag = ReturnValueTempVar() }
 
   final override string toString() { result = "#return" }
 }
 
+/**
+ * A temporary variable generated to hold the exception thrown by a `ThrowValue` instruction.
+ */
 class IRThrowVariable extends IRTempVariable {
   IRThrowVariable() { tag = ThrowTempVar() }
 
   override string getBaseString() { result = "#throw" }
 }
 
+/**
+ * A variable generated to represent the contents of a string literal. This variable acts much like
+ * a read-only global variable.
+ */
 class IRStringLiteral extends IRGeneratedVariable, TIRStringLiteral {
   Language::StringLiteral literal;
 

csharp/ql/src/semmle/code/csharp/ir/implementation/unaliased_ssa/Instruction.qll

@@ -94,12 +94,21 @@ module InstructionSanity {
   /**
    * Holds if instruction `instr` has multiple operands with tag `tag`.
    */
-  query predicate duplicateOperand(Instruction instr, OperandTag tag) {
-    strictcount(NonPhiOperand operand |
-      operand = instr.getAnOperand() and
-      operand.getOperandTag() = tag
-    ) > 1 and
-    not tag instanceof UnmodeledUseOperandTag
+  query predicate duplicateOperand(
+    Instruction instr, string message, IRFunction func, string funcText
+  ) {
+    exists(OperandTag tag, int operandCount |
+      operandCount = strictcount(NonPhiOperand operand |
+          operand = instr.getAnOperand() and
+          operand.getOperandTag() = tag
+        ) and
+      operandCount > 1 and
+      not tag instanceof UnmodeledUseOperandTag and
+      message = "Instruction has " + operandCount + " operands with tag '" + tag.toString() + "'" +
+          " in function '$@'." and
+      func = instr.getEnclosingIRFunction() and
+      funcText = Language::getIdentityString(func.getFunction())
+    )
   }
 
   /**

csharp/ql/src/semmle/code/csharp/ir/implementation/unaliased_ssa/internal/SSAConstruction.qll

@@ -865,3 +865,17 @@ private module CachedForDebugging {
     result.getTag() = var.getTag()
   }
 }
+
+module SSASanity {
+  query predicate multipleOperandMemoryLocations(
+    OldIR::MemoryOperand operand, string message, OldIR::IRFunction func, string funcText
+  ) {
+    exists(int locationCount |
+      locationCount = strictcount(Alias::getOperandMemoryLocation(operand)) and
+      locationCount > 1 and
+      func = operand.getEnclosingIRFunction() and
+      funcText = Language::getIdentityString(func.getFunction()) and
+      message = "Operand has " + locationCount.toString() + " memory accesses in function '$@'."
+    )
+  }
+}

csharp/ql/src/semmle/code/csharp/ir/implementation/unaliased_ssa/internal/SSASanity.ql

@@ -0,0 +1,8 @@
+/**
+ * @name Unaliased SSA Sanity Check
+ * @description Performs sanity checks on the SSA construction. This query should have no results.
+ * @kind table
+ * @id csharp/unaliased-ssa-sanity-check
+ */
+
+import SSASanity

csharp/ql/src/semmle/code/csharp/ir/implementation/unaliased_ssa/internal/SSASanity.qll

@@ -0,0 +1,2 @@
+private import SSAConstruction as SSA
+import SSA::SSASanity

csharp/ql/src/semmle/code/csharp/ir/internal/IntegerConstant.qll

@@ -192,3 +192,33 @@ predicate isGT(IntValue a, IntValue b) { hasValue(a) and hasValue(b) and a > b }
  */
 bindingset[a, b]
 predicate isGE(IntValue a, IntValue b) { hasValue(a) and hasValue(b) and a >= b }
+
+/**
+ * Converts the bit count in `bits` to a byte count and a bit count in the form
+ * "bytes:bits". If `bits` represents an integer number of bytes, the ":bits" section is omitted.
+ * If `bits` does not have a known value, the result is "?".
+ */
+bindingset[bits]
+string bitsToBytesAndBits(IntValue bits) {
+  exists(int bytes, int leftoverBits |
+    hasValue(bits) and
+    bytes = bits / 8 and
+    leftoverBits = bits % 8 and
+    if leftoverBits = 0 then result = bytes.toString() else result = bytes + ":" + leftoverBits
+  )
+  or
+  not hasValue(bits) and result = "?"
+}
+
+/**
+ * Gets a printable string for a bit offset with possibly unknown value.
+ */
+bindingset[bitOffset]
+string getBitOffsetString(IntValue bitOffset) {
+  if hasValue(bitOffset)
+  then
+    if bitOffset >= 0
+    then result = "+" + bitsToBytesAndBits(bitOffset)
+    else result = "-" + bitsToBytesAndBits(neg(bitOffset))
+  else result = "+?"
+}

csharp/ql/src/semmle/code/csharp/ir/internal/IntegerInterval.qll

@@ -30,5 +30,5 @@ Overlap getOverlap(IntValue defStart, IntValue defEnd, IntValue useStart, IntVal
 bindingset[start, end]
 string getIntervalString(IntValue start, IntValue end) {
   // We represent an interval has half-open, so print it as "[start..end)".
-  result = "[" + intValueToString(start) + ".." + intValueToString(end) + ")"
+  result = "[" + bitsToBytesAndBits(start) + ".." + bitsToBytesAndBits(end) + ")"
 }

csharp/ql/test/library-tests/ir/ir/unaliased_ssa_ssa_sanity.qlref

@@ -0,0 +1 @@
+semmle/code/csharp/ir/implementation/unaliased_ssa/internal/SSASanity.ql

csharp/ql/test/query-tests/Security Features/CWE-016/ASPNetMaxRequestLength.cs

@@ -0,0 +1,5 @@
+// Dummy class for extraction purposes
+public class ASPNetMaxRequestLengthDummyClass
+{
+
+}

csharp/ql/test/query-tests/Security Features/CWE-016/ASPNetMaxRequestLength.expected

@@ -0,0 +1 @@
+| bad/Web.config:4:5:4:46 | maxRequestLength=262144 | Large 'maxRequestLength' value (262144 KB). |

csharp/ql/test/query-tests/Security Features/CWE-016/ASPNetMaxRequestLength.qlref

@@ -0,0 +1 @@
+Security Features/CWE-016/ASPNetMaxRequestLength.ql

csharp/ql/test/query-tests/Security Features/CWE-016/Web.config

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="utf-8" ?>
+<configuration>
+  <system.web>
+    <httpRuntime maxRequestLength="4096" />
+  </system.web>
+</configuration>

csharp/ql/test/query-tests/Security Features/CWE-016/bad/Web.config

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="utf-8" ?>
+<configuration>
+  <system.web>
+    <httpRuntime maxRequestLength="262144" />
+  </system.web>
+</configuration>

docs/query-metadata-style-guide.md

@@ -113,7 +113,7 @@ Alert queries (`@kind problem` or `path-problem`) support two further properties
     *   `low `
     *   `medium `
     *   `high `
-    *   `very high`
+    *   `very-high`
 *   `@problem.severity`–defines the level of severity of the alert: 
     *   `error`–an issue that is likely to cause incorrect program behavior, for example a crash or vulnerability.
     *   `warning`–an issue that indicates a potential problem in the code, or makes the code fragile if another (unrelated) part of code is changed.

java/ql/src/Security/CWE/CWE-078/ExecTainted.ql

@@ -11,7 +11,7 @@
  *       external/cwe/cwe-088
  */
 
-import semmle.code.java.Expr
+import java
 import semmle.code.java.dataflow.FlowSources
 import semmle.code.java.security.ExternalProcess
 import ExecCommon

java/ql/src/Security/CWE/CWE-078/ExecUnescaped.ql

@@ -11,7 +11,7 @@
  *       external/cwe/cwe-088
  */
 
-import semmle.code.java.Expr
+import java
 import semmle.code.java.security.ExternalProcess
 import ExecCommon
 

java/ql/src/Security/CWE/CWE-089/SqlTainted.ql

@@ -10,7 +10,7 @@
  *       external/cwe/cwe-089
  */
 
-import semmle.code.java.Expr
+import java
 import semmle.code.java.dataflow.FlowSources
 import SqlInjectionLib
 import DataFlow::PathGraph

java/ql/src/Security/CWE/CWE-089/SqlUnescaped.ql

@@ -10,6 +10,7 @@
  *       external/cwe/cwe-089
  */
 
+import java
 import semmle.code.java.security.SqlUnescapedLib
 import SqlInjectionLib
 

java/ql/src/semmle/code/java/dataflow/NullGuards.qll

@@ -24,6 +24,21 @@ Expr enumConstEquality(Expr e, boolean polarity, EnumConstant c) {
   )
 }
 
+/** Gets an instanceof expression of `v` with type `type` */
+InstanceOfExpr instanceofExpr(SsaVariable v, Type type) {
+  result.getTypeName().getType() = type and
+  result.getExpr() = v.getAUse()
+}
+
+/**
+ * Gets an expression of the form `v1 == v2` or `v1 != v2`.
+ * The predicate is symmetric in `v1` and `v2`.
+ */
+EqualityTest varEqualityTestExpr(SsaVariable v1, SsaVariable v2, boolean isEqualExpr) {
+  result.hasOperands(v1.getAUse(), v2.getAUse()) and
+  isEqualExpr = result.polarity()
+}
+
 /** Gets an expression that is provably not `null`. */
 Expr clearlyNotNullExpr(Expr reason) {
   result instanceof ClassInstanceExpr and reason = result

java/ql/src/semmle/code/java/dataflow/Nullness.qll

@@ -515,6 +515,18 @@ private predicate correlatedConditions(
       cond2.getCondition() = enumConstEquality(v.getAUse(), pol2, c) and
       inverted = pol1.booleanXor(pol2)
     )
+    or
+    exists(SsaVariable v, Type type |
+      cond1.getCondition() = instanceofExpr(v, type) and
+      cond2.getCondition() = instanceofExpr(v, type) and
+      inverted = false
+    )
+    or
+    exists(SsaVariable v1, SsaVariable v2, boolean branch1, boolean branch2 |
+      cond1.getCondition() = varEqualityTestExpr(v1, v2, branch1) and
+      cond2.getCondition() = varEqualityTestExpr(v1, v2, branch2) and
+      inverted = branch1.booleanXor(branch2)
+    )
   )
 }
 

java/ql/src/semmle/code/java/dataflow/internal/DataFlowImpl.qll

@@ -464,7 +464,7 @@ private predicate simpleParameterFlow(
 ) {
   throughFlowNodeCand(node, config) and
   p = node and
-  t = getErasedRepr(node.getType()) and
+  t = getErasedNodeType(node) and
   exists(ReturnNode ret, ReturnKind kind |
     returnNodeGetEnclosingCallable(ret) = p.getEnclosingCallable() and
     kind = ret.getKind() and
@@ -475,21 +475,21 @@ private predicate simpleParameterFlow(
   exists(Node mid |
     simpleParameterFlow(p, mid, t, config) and
     localFlowStep(mid, node, config) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   throughFlowNodeCand(node, unbind(config)) and
   exists(Node mid |
     simpleParameterFlow(p, mid, _, config) and
     additionalLocalFlowStep(mid, node, config) and
-    t = getErasedRepr(node.getType())
+    t = getErasedNodeType(node)
   )
   or
   throughFlowNodeCand(node, unbind(config)) and
   exists(Node mid |
     simpleParameterFlow(p, mid, t, config) and
     localStoreReadStep(mid, node) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   // value flow through a callable
@@ -497,7 +497,7 @@ private predicate simpleParameterFlow(
   exists(Node arg |
     simpleParameterFlow(p, arg, t, config) and
     argumentValueFlowsThrough(arg, node, _) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   // flow through a callable
@@ -989,7 +989,9 @@ private class CastingNode extends Node {
  */
 private predicate flowCandFwd(Node node, boolean fromArg, AccessPathFront apf, Configuration config) {
   flowCandFwd0(node, fromArg, apf, config) and
-  if node instanceof CastingNode then compatibleTypes(node.getType(), apf.getType()) else any()
+  if node instanceof CastingNode
+  then compatibleTypes(getErasedNodeType(node), apf.getType())
+  else any()
 }
 
 /**
@@ -1010,7 +1012,7 @@ private class AccessPathFrontNilNode extends Node {
   }
 
   pragma[noinline]
-  private DataFlowType getErasedReprType() { result = getErasedRepr(this.getType()) }
+  private DataFlowType getErasedReprType() { result = getErasedNodeType(this) }
 
   /** Gets the `nil` path front for this node. */
   AccessPathFrontNil getApf() { result = TFrontNil(this.getErasedReprType()) }
@@ -1337,7 +1339,7 @@ private class AccessPathNilNode extends Node {
   AccessPathNilNode() { flowCand(this.(AccessPathFrontNilNode), _, _, _) }
 
   pragma[noinline]
-  private DataFlowType getErasedReprType() { result = getErasedRepr(this.getType()) }
+  private DataFlowType getErasedReprType() { result = getErasedNodeType(this) }
 
   /** Gets the `nil` path for this node. */
   AccessPathNil getAp() { result = TNil(this.getErasedReprType()) }
@@ -2076,7 +2078,7 @@ private module FlowExploration {
     TPartialPathNodeMk(Node node, CallContext cc, PartialAccessPath ap, Configuration config) {
       config.isSource(node) and
       cc instanceof CallContextAny and
-      ap = TPartialNil(getErasedRepr(node.getType())) and
+      ap = TPartialNil(getErasedNodeType(node)) and
       not fullBarrier(node, config) and
       exists(config.explorationLimit())
       or
@@ -2091,7 +2093,9 @@ private module FlowExploration {
     exists(PartialPathNode mid |
       partialPathStep(mid, node, cc, ap, config) and
       not fullBarrier(node, config) and
-      if node instanceof CastingNode then compatibleTypes(node.getType(), ap.getType()) else any()
+      if node instanceof CastingNode
+      then compatibleTypes(getErasedNodeType(node), ap.getType())
+      else any()
     )
   }
 
@@ -2194,7 +2198,7 @@ private module FlowExploration {
       additionalLocalFlowStep(mid.getNode(), node, config) and
       cc = mid.getCallContext() and
       mid.getAp() instanceof PartialAccessPathNil and
-      ap = TPartialNil(getErasedRepr(node.getType())) and
+      ap = TPartialNil(getErasedNodeType(node)) and
       config = mid.getConfiguration()
     )
     or
@@ -2206,7 +2210,7 @@ private module FlowExploration {
     additionalJumpStep(mid.getNode(), node, config) and
     cc instanceof CallContextAny and
     mid.getAp() instanceof PartialAccessPathNil and
-    ap = TPartialNil(getErasedRepr(node.getType())) and
+    ap = TPartialNil(getErasedNodeType(node)) and
     config = mid.getConfiguration()
     or
     partialPathStoreStep(mid, _, _, node, ap) and

java/ql/src/semmle/code/java/dataflow/internal/DataFlowImpl2.qll

@@ -464,7 +464,7 @@ private predicate simpleParameterFlow(
 ) {
   throughFlowNodeCand(node, config) and
   p = node and
-  t = getErasedRepr(node.getType()) and
+  t = getErasedNodeType(node) and
   exists(ReturnNode ret, ReturnKind kind |
     returnNodeGetEnclosingCallable(ret) = p.getEnclosingCallable() and
     kind = ret.getKind() and
@@ -475,21 +475,21 @@ private predicate simpleParameterFlow(
   exists(Node mid |
     simpleParameterFlow(p, mid, t, config) and
     localFlowStep(mid, node, config) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   throughFlowNodeCand(node, unbind(config)) and
   exists(Node mid |
     simpleParameterFlow(p, mid, _, config) and
     additionalLocalFlowStep(mid, node, config) and
-    t = getErasedRepr(node.getType())
+    t = getErasedNodeType(node)
   )
   or
   throughFlowNodeCand(node, unbind(config)) and
   exists(Node mid |
     simpleParameterFlow(p, mid, t, config) and
     localStoreReadStep(mid, node) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   // value flow through a callable
@@ -497,7 +497,7 @@ private predicate simpleParameterFlow(
   exists(Node arg |
     simpleParameterFlow(p, arg, t, config) and
     argumentValueFlowsThrough(arg, node, _) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   // flow through a callable
@@ -989,7 +989,9 @@ private class CastingNode extends Node {
  */
 private predicate flowCandFwd(Node node, boolean fromArg, AccessPathFront apf, Configuration config) {
   flowCandFwd0(node, fromArg, apf, config) and
-  if node instanceof CastingNode then compatibleTypes(node.getType(), apf.getType()) else any()
+  if node instanceof CastingNode
+  then compatibleTypes(getErasedNodeType(node), apf.getType())
+  else any()
 }
 
 /**
@@ -1010,7 +1012,7 @@ private class AccessPathFrontNilNode extends Node {
   }
 
   pragma[noinline]
-  private DataFlowType getErasedReprType() { result = getErasedRepr(this.getType()) }
+  private DataFlowType getErasedReprType() { result = getErasedNodeType(this) }
 
   /** Gets the `nil` path front for this node. */
   AccessPathFrontNil getApf() { result = TFrontNil(this.getErasedReprType()) }
@@ -1337,7 +1339,7 @@ private class AccessPathNilNode extends Node {
   AccessPathNilNode() { flowCand(this.(AccessPathFrontNilNode), _, _, _) }
 
   pragma[noinline]
-  private DataFlowType getErasedReprType() { result = getErasedRepr(this.getType()) }
+  private DataFlowType getErasedReprType() { result = getErasedNodeType(this) }
 
   /** Gets the `nil` path for this node. */
   AccessPathNil getAp() { result = TNil(this.getErasedReprType()) }
@@ -2076,7 +2078,7 @@ private module FlowExploration {
     TPartialPathNodeMk(Node node, CallContext cc, PartialAccessPath ap, Configuration config) {
       config.isSource(node) and
       cc instanceof CallContextAny and
-      ap = TPartialNil(getErasedRepr(node.getType())) and
+      ap = TPartialNil(getErasedNodeType(node)) and
       not fullBarrier(node, config) and
       exists(config.explorationLimit())
       or
@@ -2091,7 +2093,9 @@ private module FlowExploration {
     exists(PartialPathNode mid |
       partialPathStep(mid, node, cc, ap, config) and
       not fullBarrier(node, config) and
-      if node instanceof CastingNode then compatibleTypes(node.getType(), ap.getType()) else any()
+      if node instanceof CastingNode
+      then compatibleTypes(getErasedNodeType(node), ap.getType())
+      else any()
     )
   }
 
@@ -2194,7 +2198,7 @@ private module FlowExploration {
       additionalLocalFlowStep(mid.getNode(), node, config) and
       cc = mid.getCallContext() and
       mid.getAp() instanceof PartialAccessPathNil and
-      ap = TPartialNil(getErasedRepr(node.getType())) and
+      ap = TPartialNil(getErasedNodeType(node)) and
       config = mid.getConfiguration()
     )
     or
@@ -2206,7 +2210,7 @@ private module FlowExploration {
     additionalJumpStep(mid.getNode(), node, config) and
     cc instanceof CallContextAny and
     mid.getAp() instanceof PartialAccessPathNil and
-    ap = TPartialNil(getErasedRepr(node.getType())) and
+    ap = TPartialNil(getErasedNodeType(node)) and
     config = mid.getConfiguration()
     or
     partialPathStoreStep(mid, _, _, node, ap) and

java/ql/src/semmle/code/java/dataflow/internal/DataFlowImpl3.qll

@@ -464,7 +464,7 @@ private predicate simpleParameterFlow(
 ) {
   throughFlowNodeCand(node, config) and
   p = node and
-  t = getErasedRepr(node.getType()) and
+  t = getErasedNodeType(node) and
   exists(ReturnNode ret, ReturnKind kind |
     returnNodeGetEnclosingCallable(ret) = p.getEnclosingCallable() and
     kind = ret.getKind() and
@@ -475,21 +475,21 @@ private predicate simpleParameterFlow(
   exists(Node mid |
     simpleParameterFlow(p, mid, t, config) and
     localFlowStep(mid, node, config) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   throughFlowNodeCand(node, unbind(config)) and
   exists(Node mid |
     simpleParameterFlow(p, mid, _, config) and
     additionalLocalFlowStep(mid, node, config) and
-    t = getErasedRepr(node.getType())
+    t = getErasedNodeType(node)
   )
   or
   throughFlowNodeCand(node, unbind(config)) and
   exists(Node mid |
     simpleParameterFlow(p, mid, t, config) and
     localStoreReadStep(mid, node) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   // value flow through a callable
@@ -497,7 +497,7 @@ private predicate simpleParameterFlow(
   exists(Node arg |
     simpleParameterFlow(p, arg, t, config) and
     argumentValueFlowsThrough(arg, node, _) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   // flow through a callable
@@ -989,7 +989,9 @@ private class CastingNode extends Node {
  */
 private predicate flowCandFwd(Node node, boolean fromArg, AccessPathFront apf, Configuration config) {
   flowCandFwd0(node, fromArg, apf, config) and
-  if node instanceof CastingNode then compatibleTypes(node.getType(), apf.getType()) else any()
+  if node instanceof CastingNode
+  then compatibleTypes(getErasedNodeType(node), apf.getType())
+  else any()
 }
 
 /**
@@ -1010,7 +1012,7 @@ private class AccessPathFrontNilNode extends Node {
   }
 
   pragma[noinline]
-  private DataFlowType getErasedReprType() { result = getErasedRepr(this.getType()) }
+  private DataFlowType getErasedReprType() { result = getErasedNodeType(this) }
 
   /** Gets the `nil` path front for this node. */
   AccessPathFrontNil getApf() { result = TFrontNil(this.getErasedReprType()) }
@@ -1337,7 +1339,7 @@ private class AccessPathNilNode extends Node {
   AccessPathNilNode() { flowCand(this.(AccessPathFrontNilNode), _, _, _) }
 
   pragma[noinline]
-  private DataFlowType getErasedReprType() { result = getErasedRepr(this.getType()) }
+  private DataFlowType getErasedReprType() { result = getErasedNodeType(this) }
 
   /** Gets the `nil` path for this node. */
   AccessPathNil getAp() { result = TNil(this.getErasedReprType()) }
@@ -2076,7 +2078,7 @@ private module FlowExploration {
     TPartialPathNodeMk(Node node, CallContext cc, PartialAccessPath ap, Configuration config) {
       config.isSource(node) and
       cc instanceof CallContextAny and
-      ap = TPartialNil(getErasedRepr(node.getType())) and
+      ap = TPartialNil(getErasedNodeType(node)) and
       not fullBarrier(node, config) and
       exists(config.explorationLimit())
       or
@@ -2091,7 +2093,9 @@ private module FlowExploration {
     exists(PartialPathNode mid |
       partialPathStep(mid, node, cc, ap, config) and
       not fullBarrier(node, config) and
-      if node instanceof CastingNode then compatibleTypes(node.getType(), ap.getType()) else any()
+      if node instanceof CastingNode
+      then compatibleTypes(getErasedNodeType(node), ap.getType())
+      else any()
     )
   }
 
@@ -2194,7 +2198,7 @@ private module FlowExploration {
       additionalLocalFlowStep(mid.getNode(), node, config) and
       cc = mid.getCallContext() and
       mid.getAp() instanceof PartialAccessPathNil and
-      ap = TPartialNil(getErasedRepr(node.getType())) and
+      ap = TPartialNil(getErasedNodeType(node)) and
       config = mid.getConfiguration()
     )
     or
@@ -2206,7 +2210,7 @@ private module FlowExploration {
     additionalJumpStep(mid.getNode(), node, config) and
     cc instanceof CallContextAny and
     mid.getAp() instanceof PartialAccessPathNil and
-    ap = TPartialNil(getErasedRepr(node.getType())) and
+    ap = TPartialNil(getErasedNodeType(node)) and
     config = mid.getConfiguration()
     or
     partialPathStoreStep(mid, _, _, node, ap) and

java/ql/src/semmle/code/java/dataflow/internal/DataFlowImpl4.qll

@@ -464,7 +464,7 @@ private predicate simpleParameterFlow(
 ) {
   throughFlowNodeCand(node, config) and
   p = node and
-  t = getErasedRepr(node.getType()) and
+  t = getErasedNodeType(node) and
   exists(ReturnNode ret, ReturnKind kind |
     returnNodeGetEnclosingCallable(ret) = p.getEnclosingCallable() and
     kind = ret.getKind() and
@@ -475,21 +475,21 @@ private predicate simpleParameterFlow(
   exists(Node mid |
     simpleParameterFlow(p, mid, t, config) and
     localFlowStep(mid, node, config) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   throughFlowNodeCand(node, unbind(config)) and
   exists(Node mid |
     simpleParameterFlow(p, mid, _, config) and
     additionalLocalFlowStep(mid, node, config) and
-    t = getErasedRepr(node.getType())
+    t = getErasedNodeType(node)
   )
   or
   throughFlowNodeCand(node, unbind(config)) and
   exists(Node mid |
     simpleParameterFlow(p, mid, t, config) and
     localStoreReadStep(mid, node) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   // value flow through a callable
@@ -497,7 +497,7 @@ private predicate simpleParameterFlow(
   exists(Node arg |
     simpleParameterFlow(p, arg, t, config) and
     argumentValueFlowsThrough(arg, node, _) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   // flow through a callable
@@ -989,7 +989,9 @@ private class CastingNode extends Node {
  */
 private predicate flowCandFwd(Node node, boolean fromArg, AccessPathFront apf, Configuration config) {
   flowCandFwd0(node, fromArg, apf, config) and
-  if node instanceof CastingNode then compatibleTypes(node.getType(), apf.getType()) else any()
+  if node instanceof CastingNode
+  then compatibleTypes(getErasedNodeType(node), apf.getType())
+  else any()
 }
 
 /**
@@ -1010,7 +1012,7 @@ private class AccessPathFrontNilNode extends Node {
   }
 
   pragma[noinline]
-  private DataFlowType getErasedReprType() { result = getErasedRepr(this.getType()) }
+  private DataFlowType getErasedReprType() { result = getErasedNodeType(this) }
 
   /** Gets the `nil` path front for this node. */
   AccessPathFrontNil getApf() { result = TFrontNil(this.getErasedReprType()) }
@@ -1337,7 +1339,7 @@ private class AccessPathNilNode extends Node {
   AccessPathNilNode() { flowCand(this.(AccessPathFrontNilNode), _, _, _) }
 
   pragma[noinline]
-  private DataFlowType getErasedReprType() { result = getErasedRepr(this.getType()) }
+  private DataFlowType getErasedReprType() { result = getErasedNodeType(this) }
 
   /** Gets the `nil` path for this node. */
   AccessPathNil getAp() { result = TNil(this.getErasedReprType()) }
@@ -2076,7 +2078,7 @@ private module FlowExploration {
     TPartialPathNodeMk(Node node, CallContext cc, PartialAccessPath ap, Configuration config) {
       config.isSource(node) and
       cc instanceof CallContextAny and
-      ap = TPartialNil(getErasedRepr(node.getType())) and
+      ap = TPartialNil(getErasedNodeType(node)) and
       not fullBarrier(node, config) and
       exists(config.explorationLimit())
       or
@@ -2091,7 +2093,9 @@ private module FlowExploration {
     exists(PartialPathNode mid |
       partialPathStep(mid, node, cc, ap, config) and
       not fullBarrier(node, config) and
-      if node instanceof CastingNode then compatibleTypes(node.getType(), ap.getType()) else any()
+      if node instanceof CastingNode
+      then compatibleTypes(getErasedNodeType(node), ap.getType())
+      else any()
     )
   }
 
@@ -2194,7 +2198,7 @@ private module FlowExploration {
       additionalLocalFlowStep(mid.getNode(), node, config) and
       cc = mid.getCallContext() and
       mid.getAp() instanceof PartialAccessPathNil and
-      ap = TPartialNil(getErasedRepr(node.getType())) and
+      ap = TPartialNil(getErasedNodeType(node)) and
       config = mid.getConfiguration()
     )
     or
@@ -2206,7 +2210,7 @@ private module FlowExploration {
     additionalJumpStep(mid.getNode(), node, config) and
     cc instanceof CallContextAny and
     mid.getAp() instanceof PartialAccessPathNil and
-    ap = TPartialNil(getErasedRepr(node.getType())) and
+    ap = TPartialNil(getErasedNodeType(node)) and
     config = mid.getConfiguration()
     or
     partialPathStoreStep(mid, _, _, node, ap) and

java/ql/src/semmle/code/java/dataflow/internal/DataFlowImpl5.qll

@@ -464,7 +464,7 @@ private predicate simpleParameterFlow(
 ) {
   throughFlowNodeCand(node, config) and
   p = node and
-  t = getErasedRepr(node.getType()) and
+  t = getErasedNodeType(node) and
   exists(ReturnNode ret, ReturnKind kind |
     returnNodeGetEnclosingCallable(ret) = p.getEnclosingCallable() and
     kind = ret.getKind() and
@@ -475,21 +475,21 @@ private predicate simpleParameterFlow(
   exists(Node mid |
     simpleParameterFlow(p, mid, t, config) and
     localFlowStep(mid, node, config) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   throughFlowNodeCand(node, unbind(config)) and
   exists(Node mid |
     simpleParameterFlow(p, mid, _, config) and
     additionalLocalFlowStep(mid, node, config) and
-    t = getErasedRepr(node.getType())
+    t = getErasedNodeType(node)
   )
   or
   throughFlowNodeCand(node, unbind(config)) and
   exists(Node mid |
     simpleParameterFlow(p, mid, t, config) and
     localStoreReadStep(mid, node) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   // value flow through a callable
@@ -497,7 +497,7 @@ private predicate simpleParameterFlow(
   exists(Node arg |
     simpleParameterFlow(p, arg, t, config) and
     argumentValueFlowsThrough(arg, node, _) and
-    compatibleTypes(t, node.getType())
+    compatibleTypes(t, getErasedNodeType(node))
   )
   or
   // flow through a callable
@@ -989,7 +989,9 @@ private class CastingNode extends Node {
  */
 private predicate flowCandFwd(Node node, boolean fromArg, AccessPathFront apf, Configuration config) {
   flowCandFwd0(node, fromArg, apf, config) and
-  if node instanceof CastingNode then compatibleTypes(node.getType(), apf.getType()) else any()
+  if node instanceof CastingNode
+  then compatibleTypes(getErasedNodeType(node), apf.getType())
+  else any()
 }
 
 /**
@@ -1010,7 +1012,7 @@ private class AccessPathFrontNilNode extends Node {
   }
 
   pragma[noinline]
-  private DataFlowType getErasedReprType() { result = getErasedRepr(this.getType()) }
+  private DataFlowType getErasedReprType() { result = getErasedNodeType(this) }
 
   /** Gets the `nil` path front for this node. */
   AccessPathFrontNil getApf() { result = TFrontNil(this.getErasedReprType()) }
@@ -1337,7 +1339,7 @@ private class AccessPathNilNode extends Node {
   AccessPathNilNode() { flowCand(this.(AccessPathFrontNilNode), _, _, _) }
 
   pragma[noinline]
-  private DataFlowType getErasedReprType() { result = getErasedRepr(this.getType()) }
+  private DataFlowType getErasedReprType() { result = getErasedNodeType(this) }
 
   /** Gets the `nil` path for this node. */
   AccessPathNil getAp() { result = TNil(this.getErasedReprType()) }
@@ -2076,7 +2078,7 @@ private module FlowExploration {
     TPartialPathNodeMk(Node node, CallContext cc, PartialAccessPath ap, Configuration config) {
       config.isSource(node) and
       cc instanceof CallContextAny and
-      ap = TPartialNil(getErasedRepr(node.getType())) and
+      ap = TPartialNil(getErasedNodeType(node)) and
       not fullBarrier(node, config) and
       exists(config.explorationLimit())
       or
@@ -2091,7 +2093,9 @@ private module FlowExploration {
     exists(PartialPathNode mid |
       partialPathStep(mid, node, cc, ap, config) and
       not fullBarrier(node, config) and
-      if node instanceof CastingNode then compatibleTypes(node.getType(), ap.getType()) else any()
+      if node instanceof CastingNode
+      then compatibleTypes(getErasedNodeType(node), ap.getType())
+      else any()
     )
   }
 
@@ -2194,7 +2198,7 @@ private module FlowExploration {
       additionalLocalFlowStep(mid.getNode(), node, config) and
       cc = mid.getCallContext() and
       mid.getAp() instanceof PartialAccessPathNil and
-      ap = TPartialNil(getErasedRepr(node.getType())) and
+      ap = TPartialNil(getErasedNodeType(node)) and
       config = mid.getConfiguration()
     )
     or
@@ -2206,7 +2210,7 @@ private module FlowExploration {
     additionalJumpStep(mid.getNode(), node, config) and
     cc instanceof CallContextAny and
     mid.getAp() instanceof PartialAccessPathNil and
-    ap = TPartialNil(getErasedRepr(node.getType())) and
+    ap = TPartialNil(getErasedNodeType(node)) and
     config = mid.getConfiguration()
     or
     partialPathStoreStep(mid, _, _, node, ap) and

java/ql/src/semmle/code/java/dataflow/internal/DataFlowImplCommon.qll

@@ -57,14 +57,14 @@ private module ImplCommon {
         exists(Node mid |
           parameterValueFlowCand(p, mid) and
           step(mid, node) and
-          compatibleTypes(p.getType(), node.getType())
+          compatibleTypes(getErasedNodeType(p), getErasedNodeType(node))
         )
         or
         // flow through a callable
         exists(Node arg |
           parameterValueFlowCand(p, arg) and
           argumentValueFlowsThroughCand(arg, node) and
-          compatibleTypes(p.getType(), node.getType())
+          compatibleTypes(getErasedNodeType(p), getErasedNodeType(node))
         )
       }
 
@@ -95,7 +95,7 @@ private module ImplCommon {
           argumentValueFlowsThroughCand0(call, arg, kind)
         |
           out = getAnOutNode(call, kind) and
-          compatibleTypes(arg.getType(), out.getType())
+          compatibleTypes(getErasedNodeType(arg), getErasedNodeType(out))
         )
       }
 
@@ -183,7 +183,7 @@ private module ImplCommon {
         exists(Node mid |
           parameterValueFlow(p, mid, cc) and
           step(mid, node) and
-          compatibleTypes(p.getType(), node.getType()) and
+          compatibleTypes(getErasedNodeType(p), getErasedNodeType(node)) and
           not isUnreachableInCall(node, cc.(CallContextSpecificCall).getCall())
         )
         or
@@ -191,7 +191,7 @@ private module ImplCommon {
         exists(Node arg |
           parameterValueFlow(p, arg, cc) and
           argumentValueFlowsThrough(arg, node, cc) and
-          compatibleTypes(p.getType(), node.getType()) and
+          compatibleTypes(getErasedNodeType(p), getErasedNodeType(node)) and
           not isUnreachableInCall(node, cc.(CallContextSpecificCall).getCall())
         )
       }
@@ -226,7 +226,7 @@ private module ImplCommon {
         |
           out = getAnOutNode(call, kind) and
           not isUnreachableInCall(out, cc.(CallContextSpecificCall).getCall()) and
-          compatibleTypes(arg.getType(), out.getType())
+          compatibleTypes(getErasedNodeType(arg), getErasedNodeType(out))
         )
       }
     }
@@ -260,7 +260,7 @@ private module ImplCommon {
       exists(Node mid |
         parameterValueFlowNoCtx(p, mid) and
         localValueStep(mid, node) and
-        compatibleTypes(p.getType(), node.getType())
+        compatibleTypes(getErasedNodeType(p), getErasedNodeType(node))
       )
     }
 
@@ -296,8 +296,8 @@ private module ImplCommon {
         setterCall(call, i1, i2, f) and
         node1.(ArgumentNode).argumentOf(call, i1) and
         node2.getPreUpdateNode().(ArgumentNode).argumentOf(call, i2) and
-        compatibleTypes(node1.getTypeBound(), f.getType()) and
-        compatibleTypes(node2.getTypeBound(), f.getContainerType())
+        compatibleTypes(getErasedNodeTypeBound(node1), f.getType()) and
+        compatibleTypes(getErasedNodeTypeBound(node2), f.getContainerType())
       )
     }
 
@@ -333,8 +333,8 @@ private module ImplCommon {
       exists(DataFlowCall call, ReturnKind kind |
         storeReturn0(call, kind, node1, f) and
         node2 = getAnOutNode(call, kind) and
-        compatibleTypes(node1.getTypeBound(), f.getType()) and
-        compatibleTypes(node2.getTypeBound(), f.getContainerType())
+        compatibleTypes(getErasedNodeTypeBound(node1), f.getType()) and
+        compatibleTypes(getErasedNodeTypeBound(node2), f.getContainerType())
       )
     }
 
@@ -365,8 +365,8 @@ private module ImplCommon {
       exists(DataFlowCall call, ReturnKind kind |
         read0(call, kind, node1, f) and
         node2 = getAnOutNode(call, kind) and
-        compatibleTypes(node1.getTypeBound(), f.getContainerType()) and
-        compatibleTypes(node2.getTypeBound(), f.getType())
+        compatibleTypes(getErasedNodeTypeBound(node1), f.getContainerType()) and
+        compatibleTypes(getErasedNodeTypeBound(node2), f.getType())
       )
     }
 
@@ -384,7 +384,7 @@ private module ImplCommon {
         store(node1, f, mid1) and
         localValueStep*(mid1, mid2) and
         read(mid2, f, node2) and
-        compatibleTypes(node1.getTypeBound(), node2.getTypeBound())
+        compatibleTypes(getErasedNodeTypeBound(node1), getErasedNodeTypeBound(node2))
       )
     }
 
@@ -405,14 +405,14 @@ private module ImplCommon {
         exists(Node mid |
           parameterValueFlowCand(p, mid) and
           step(mid, node) and
-          compatibleTypes(p.getType(), node.getType())
+          compatibleTypes(getErasedNodeType(p), getErasedNodeType(node))
         )
         or
         // flow through a callable
         exists(Node arg |
           parameterValueFlowCand(p, arg) and
           argumentValueFlowsThroughCand(arg, node) and
-          compatibleTypes(p.getType(), node.getType())
+          compatibleTypes(getErasedNodeType(p), getErasedNodeType(node))
         )
       }
 
@@ -443,7 +443,7 @@ private module ImplCommon {
           argumentValueFlowsThroughCand0(call, arg, kind)
         |
           out = getAnOutNode(call, kind) and
-          compatibleTypes(arg.getType(), out.getType())
+          compatibleTypes(getErasedNodeType(arg), getErasedNodeType(out))
         )
       }
 
@@ -531,7 +531,7 @@ private module ImplCommon {
         exists(Node mid |
           parameterValueFlow(p, mid, cc) and
           step(mid, node) and
-          compatibleTypes(p.getType(), node.getType()) and
+          compatibleTypes(getErasedNodeType(p), getErasedNodeType(node)) and
           not isUnreachableInCall(node, cc.(CallContextSpecificCall).getCall())
         )
         or
@@ -539,7 +539,7 @@ private module ImplCommon {
         exists(Node arg |
           parameterValueFlow(p, arg, cc) and
           argumentValueFlowsThrough(arg, node, cc) and
-          compatibleTypes(p.getType(), node.getType()) and
+          compatibleTypes(getErasedNodeType(p), getErasedNodeType(node)) and
           not isUnreachableInCall(node, cc.(CallContextSpecificCall).getCall())
         )
       }
@@ -574,7 +574,7 @@ private module ImplCommon {
         |
           out = getAnOutNode(call, kind) and
           not isUnreachableInCall(out, cc.(CallContextSpecificCall).getCall()) and
-          compatibleTypes(arg.getType(), out.getType())
+          compatibleTypes(getErasedNodeType(arg), getErasedNodeType(out))
         )
       }
     }
@@ -860,4 +860,10 @@ private module ImplCommon {
     or
     result = viableCallable(call) and cc instanceof CallContextReturn
   }
+
+  pragma[noinline]
+  DataFlowType getErasedNodeType(Node n) { result = getErasedRepr(n.getType()) }
+
+  pragma[noinline]
+  DataFlowType getErasedNodeTypeBound(Node n) { result = getErasedRepr(n.getTypeBound()) }
 }

java/ql/test/query-tests/Nullness/B.java

@@ -324,4 +324,51 @@ public class B {
     if (x != null) y.hashCode(); // OK
     if (y != null) x.hashCode(); // OK
   }
+
+  public void corrConds3(Object y) {
+    Object x = null;
+    if(y instanceof String) {
+      x = new Object();
+    }
+    if(y instanceof String) {
+      x.hashCode(); // OK
+    }
+  }
+
+  public void corrConds4(Object y) {
+    Object x = null;
+    if(!(y instanceof String)) {
+      x = new Object();
+    }
+    if(!(y instanceof String)) {
+      x.hashCode(); // OK
+    }
+  }
+
+  public void corrConds5(Object y, Object z) {
+    Object x = null;
+    if(y == z) {
+      x = new Object();
+    }
+    if(y == z) {
+      x.hashCode(); // OK
+    }
+
+    Object x2 = null;
+    if(y != z) {
+      x2 = new Object();
+    }
+    if(y != z) {
+      x2.hashCode(); // OK
+    }
+
+    Object x3 = null;
+    if(y != z) {
+      x3 = new Object();
+    }
+    if(!(y == z)) {
+      x3.hashCode(); // OK
+    }
+  }
+
 }

javascript/ql/src/Statements/UseOfReturnlessFunction.ql

@@ -222,6 +222,7 @@ where
   not lastStatementHasNoEffect(func) and
   // anonymous one-shot closure. Those are used in weird ways and we ignore them.
   not oneshotClosure(call) and
-  not hasNonVoidReturnType(func)
+  not hasNonVoidReturnType(func) and
+  not call.getEnclosingExpr() instanceof SuperCall
 select
   call, msg, func, name

javascript/ql/src/javascript.qll

@@ -76,6 +76,7 @@ import semmle.javascript.frameworks.Electron
 import semmle.javascript.frameworks.Files
 import semmle.javascript.frameworks.Firebase
 import semmle.javascript.frameworks.jQuery
+import semmle.javascript.frameworks.Handlebars
 import semmle.javascript.frameworks.LodashUnderscore
 import semmle.javascript.frameworks.Logging
 import semmle.javascript.frameworks.HttpFrameworks

javascript/ql/src/semmle/javascript/frameworks/Handlebars.qll

@@ -0,0 +1,29 @@
+/**
+ * Provides classes for working with Handlebars code.
+ */
+
+import javascript
+
+module Handlebars {
+  /**
+   * A reference to the Handlebars library. 
+   */
+  class Handlebars extends DataFlow::SourceNode {
+    Handlebars() {
+      this.accessesGlobal("handlebars")
+      or
+      this.accessesGlobal("Handlebars")
+      or
+      this = DataFlow::moduleImport("handlebars")
+      or
+      this.hasUnderlyingType("Handlebars")
+    }
+  }
+
+  /**
+   * A new instantiation of a Handlebars.SafeString.
+   */
+  class SafeString extends DataFlow::NewNode {
+    SafeString() { this = any(Handlebars h).getAConstructorInvocation("SafeString") }
+  }
+}

javascript/ql/src/semmle/javascript/security/dataflow/Xss.qll

@@ -95,6 +95,8 @@ module DomBasedXss {
         mcn.getMethodName() = m and
         this = mcn.getArgument(1)
       )
+      or
+      this = any(Handlebars::SafeString s).getAnArgument()
     }
   }
 

javascript/ql/test/query-tests/Security/CWE-079/Xss.expected

@@ -315,6 +315,9 @@ nodes
 | tst.js:285:59:285:65 | tainted |
 | tst.js:285:59:285:65 | tainted |
 | tst.js:285:59:285:65 | tainted |
+| tst.js:297:35:297:42 | location |
+| tst.js:297:35:297:42 | location |
+| tst.js:297:35:297:42 | location |
 | v-html.vue:2:8:2:23 | v-html=tainted |
 | v-html.vue:2:8:2:23 | v-html=tainted |
 | v-html.vue:6:42:6:58 | document.location |
@@ -604,6 +607,7 @@ edges
 | tst.js:282:19:282:29 | window.name | tst.js:282:9:282:29 | tainted |
 | tst.js:282:19:282:29 | window.name | tst.js:282:9:282:29 | tainted |
 | tst.js:285:59:285:65 | tainted | tst.js:285:59:285:65 | tainted |
+| tst.js:297:35:297:42 | location | tst.js:297:35:297:42 | location |
 | v-html.vue:6:42:6:58 | document.location | v-html.vue:2:8:2:23 | v-html=tainted |
 | v-html.vue:6:42:6:58 | document.location | v-html.vue:2:8:2:23 | v-html=tainted |
 | v-html.vue:6:42:6:58 | document.location | v-html.vue:2:8:2:23 | v-html=tainted |
@@ -693,6 +697,7 @@ edges
 | tst.js:285:59:285:65 | tainted | tst.js:282:9:282:29 | tainted | tst.js:285:59:285:65 | tainted | Cross-site scripting vulnerability due to $@. | tst.js:282:9:282:29 | tainted | user-provided value |
 | tst.js:285:59:285:65 | tainted | tst.js:282:19:282:29 | window.name | tst.js:285:59:285:65 | tainted | Cross-site scripting vulnerability due to $@. | tst.js:282:19:282:29 | window.name | user-provided value |
 | tst.js:285:59:285:65 | tainted | tst.js:285:59:285:65 | tainted | tst.js:285:59:285:65 | tainted | Cross-site scripting vulnerability due to $@. | tst.js:285:59:285:65 | tainted | user-provided value |
+| tst.js:297:35:297:42 | location | tst.js:297:35:297:42 | location | tst.js:297:35:297:42 | location | Cross-site scripting vulnerability due to $@. | tst.js:297:35:297:42 | location | user-provided value |
 | v-html.vue:2:8:2:23 | v-html=tainted | v-html.vue:6:42:6:58 | document.location | v-html.vue:2:8:2:23 | v-html=tainted | Cross-site scripting vulnerability due to $@. | v-html.vue:6:42:6:58 | document.location | user-provided value |
 | winjs.js:3:43:3:49 | tainted | winjs.js:2:17:2:33 | document.location | winjs.js:3:43:3:49 | tainted | Cross-site scripting vulnerability due to $@. | winjs.js:2:17:2:33 | document.location | user-provided value |
 | winjs.js:4:43:4:49 | tainted | winjs.js:2:17:2:33 | document.location | winjs.js:4:43:4:49 | tainted | Cross-site scripting vulnerability due to $@. | winjs.js:2:17:2:33 | document.location | user-provided value |

javascript/ql/test/query-tests/Security/CWE-079/tst.js

@@ -292,3 +292,7 @@ function flowThroughPropertyNames() {
     for (var p in obj)
       $(p); // OK
 }
+
+function handlebarsSafeString() {
+	return new Handlebars.SafeString(location); // NOT OK!	
+}