[clang] Thread safety analysis: Fix a bug in handling temporary constructors (PR #74020)

[Aaron Puchert via cfe-commits]

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@@ -1544,7 +1544,10 @@ class BuildLockset : public ConstStmtVisitor<BuildLockset> {
   // The fact set for the function on exit.
   const FactSet &FunctionExitFSet;
   /// Maps constructed objects to `this` placeholder prior to initialization.
-  llvm::SmallDenseMap<const Expr *, til::LiteralPtr *> ConstructedObjects;
+  /// The map lives longer than this builder so this is a reference to an
+  /// existing one. The map lives so long as the CFG while this builder is for
+  /// one CFG block.
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aaronpuchert wrote:

It's probably sufficient to explain this in the commit message.

https://github.com/llvm/llvm-project/pull/74020