[clang] Diagnose misuse of the cleanup attribute (PR #80040)

[Erich Keane via cfe-commits]

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@@ -3780,6 +3780,30 @@ static void handleCleanupAttr(Sema &S, Decl *D, const ParsedAttr &AL) {
       << NI.getName() << ParamTy << Ty;
     return;
   }
+  VarDecl *VD = cast<VarDecl>(D);
+  // Create a reference to the variable declaration. This is a fake/dummy
+  // reference.
+  DeclRefExpr *VariableReference = DeclRefExpr::Create(
+      S.Context, NestedNameSpecifierLoc{}, SourceLocation{Loc}, VD, false,
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erichkeane wrote:

Also note, Loc is the location of the attribute itself, and is probably not what you want to make the location here.  I would THINK we want the diagnostic to point to the function instead... WDYT?

https://github.com/llvm/llvm-project/pull/80040