[clang] [Clang] Diagnose require_explicit_initialization for C tentative definitions (PR #234210)

[Pathri Vidya Praveen via cfe-commits]

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@@ -1550,6 +1550,20 @@ void Sema::ActOnEndOfTranslationUnit() {
       Diag(VD->getLocation(), DiagID) << Type << EmitCppCompat;
     }
 
+    // Uncompleted tentative definitions are zero-initialized (C17 6.9.2p2) so
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PathriVidyaPraveen wrote:

Done, thanks!

https://github.com/llvm/llvm-project/pull/234210