C++: Fix bad join in 'definitionOf'.

cpp/ql/lib/definitions.qll

@@ -123,6 +123,13 @@ private predicate constructorCallTypeMention(ConstructorCall cc, TypeMention tm)
   )
 }
 
+/** Holds if `loc` has the container `container` and is on the line starting at `startLine`. */
+pragma[nomagic]
+private predicate hasContainerAndStartLine(Location loc, Container container, int startLine) {
+  loc.getStartLine() = startLine and
+  loc.getContainer() = container
+}
+
 /**
  * Gets an element, of kind `kind`, that element `e` uses, if any.
  * Attention: This predicate yields multiple definitions for a single location.
@@ -184,11 +191,9 @@ Top definitionOf(Top e, string kind) {
     kind = "I" and
     result = e.(Include).getIncludedFile() and
     // exclude `#include` directives containing macros
-    not exists(MacroInvocation mi, Location l1, Location l2 |
-      l1 = e.(Include).getLocation() and
-      l2 = mi.getLocation() and
-      l1.getContainer() = l2.getContainer() and
-      l1.getStartLine() = l2.getStartLine()
+    not exists(MacroInvocation mi, Container container, int startLine |
+      hasContainerAndStartLine(e.(Include).getLocation(), container, startLine) and
+      hasContainerAndStartLine(mi.getLocation(), container, startLine)
       // (an #include directive must be always on it's own line)
     )
   ) and

cpp/ql/lib/semmle/code/cpp/Location.qll

@@ -10,12 +10,14 @@ import semmle.code.cpp.File
  */
 class Location extends @location {
   /** Gets the container corresponding to this location. */
+  pragma[nomagic]
   Container getContainer() { this.fullLocationInfo(result, _, _, _, _) }
 
   /** Gets the file corresponding to this location, if any. */
   File getFile() { result = this.getContainer() }
 
   /** Gets the 1-based line number (inclusive) where this location starts. */
+  pragma[nomagic]
   int getStartLine() { this.fullLocationInfo(_, result, _, _, _) }
 
   /** Gets the 1-based column number (inclusive) where this location starts. */