Extract container of adapter function as compiler generated

java/kotlin-extractor/src/main/kotlin/KotlinFileExtractor.kt

@@ -943,6 +943,10 @@ open class KotlinFileExtractor(
                         extractLocalTypeDeclStmt(classId, s, callable, parent, idx)
                         val ids = getLocallyVisibleFunctionLabels(s)
                         tw.writeKtLocalFunction(ids.function)
+
+                        if (s.origin == IrDeclarationOrigin.ADAPTER_FOR_CALLABLE_REFERENCE) {
+                            tw.writeCompiler_generated(classId, 1)
+                        }
                     } else {
                         logger.errorElement("Expected to find local function", s)
                     }

java/ql/lib/config/semmlecode.dbscheme

@@ -1222,3 +1222,9 @@ ktPropertyDelegates(
   unique int id: @kt_property ref,
   unique int variableId: @variable ref
 )
+
+compiler_generated(
+  unique int id: @top ref,
+  int kind: int ref
+  // 1: Kotlin declaring classes of adapter functions
+);

java/ql/src/Violations of Best Practice/Dead Code/DeadRefTypes.ql

@@ -50,7 +50,9 @@ predicate dead(RefType dead) {
   // Exclude classes that look like they may be reflectively constructed.
   not dead.getAnAnnotation() instanceof ReflectiveAccessAnnotation and
   // Insist all source ancestors are dead as well.
-  forall(RefType t | t.fromSource() and t = getASuperTypePlus(dead) | dead(t))
+  forall(RefType t | t.fromSource() and t = getASuperTypePlus(dead) | dead(t)) and
+  // Exclude compiler generated classes (e.g. declaring type of adapter functions in Kotlin)
+  not compiler_generated(dead, _)
 }
 
 from RefType t, string kind

java/ql/test/kotlin/library-tests/reflection/reflection.expected

@@ -228,3 +228,5 @@ modifiers
 | reflection.kt:116:40:116:44 | ...::... | reflection.kt:116:40:116:44 | invoke | override |
 | reflection.kt:116:40:116:44 | ...::... | reflection.kt:116:40:116:44 | invoke | public |
 | reflection.kt:126:9:126:13 | ...::... | reflection.kt:126:9:126:13 | invoke | public |
+compGenerated
+| reflection.kt:126:9:126:13 |  | 1 |

java/ql/test/kotlin/library-tests/reflection/reflection.ql

@@ -86,3 +86,5 @@ query predicate modifiers(ClassInstanceExpr e, Method m, string modifier) {
   e.getAnonymousClass().getAMethod() = m and
   m.hasModifier(modifier)
 }
+
+query predicate compGenerated(Top t, int i) { compiler_generated(t, i) }