[clang] [clang-tools-extra] [llvm] [clang] WIP: Improved Context Declaration tracking (PR #107942)

[Younan Zhang via cfe-commits]

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@@ -19998,9 +20054,9 @@ bool Sema::DiagIfReachable(SourceLocation Loc, ArrayRef<const Stmt *> Stmts,
   // static data member is not syntactically a constant evaluated constant,
   // but nonetheless is always required to be a constant expression, so we
   // can skip diagnosing.
-  // FIXME: Using the mangling context here is a hack.
-  if (auto *VD = dyn_cast_or_null<VarDecl>(
-          ExprEvalContexts.back().ManglingContextDecl)) {
+  if (auto ContextDecl = currentEvaluationContext().ContextDecl;
+      auto *VD =
+          dyn_cast_or_null<VarDecl>(ContextDecl ? *ContextDecl : nullptr)) {
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zyn0217 wrote:

dyn_cast_if_present, if we have to touch it anyway :)

https://github.com/llvm/llvm-project/pull/107942