[clang] [C] Disallow declarations where a statement is required (PR #92908)

[via cfe-commits]

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@@ -239,7 +239,10 @@ StmtResult Parser::ParseStatementOrDeclarationAfterAttributes(
     auto IsStmtAttr = [](ParsedAttr &Attr) { return Attr.isStmtAttr(); };
     bool AllAttrsAreStmtAttrs = llvm::all_of(CXX11Attrs, IsStmtAttr) &&
                                 llvm::all_of(GNUAttrs, IsStmtAttr);
-    if (((GNUAttributeLoc.isValid() && !(HaveAttrs && AllAttrsAreStmtAttrs)) ||
+    if ((getLangOpts().CPlusPlus || getLangOpts().MicrosoftExt ||
+         (StmtCtx & ParsedStmtContext::AllowDeclarationsInC) !=
+             ParsedStmtContext()) &&
+        ((GNUAttributeLoc.isValid() && !(HaveAttrs && AllAttrsAreStmtAttrs)) ||
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cor3ntin wrote:

Can you add a standard quote?

https://github.com/llvm/llvm-project/pull/92908