[clang] [Clang][Sema] Allow counted_by on void* as GNU extension (PR #164737)

[Kees Cook via cfe-commits]

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@@ -1211,11 +1211,13 @@ llvm::Value *CodeGenFunction::emitCountedByPointerSize(
         getContext().getTypeSizeInChars(ElementTy->getPointeeType());
 
     if (ElementSize.isZero()) {
-      // This might be a __sized_by on a 'void *', which counts bytes, not
-      // elements.
+      // This might be a __sized_by (or __counted_by in GNU mode) on a
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kees wrote:

Oops! Yes, I will adjust this.

https://github.com/llvm/llvm-project/pull/164737