[clang] Warn when unique objects might be duplicated in shared libraries (PR #117622)

[Hans Wennborg via cfe-commits]

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@@ -13374,6 +13374,62 @@ void Sema::checkNonTrivialCUnion(QualType QT, SourceLocation Loc,
         .visit(QT, nullptr, false);
 }
 
+bool Sema::GloballyUniqueObjectMightBeAccidentallyDuplicated(
+    const VarDecl *Dcl) {
+  if (!Dcl || !getLangOpts().CPlusPlus)
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zmodem wrote:

can `Dcl` really be null?

https://github.com/llvm/llvm-project/pull/117622