[clang] [clang] Add support for consteval null terminated strings (PR #173140)

[Corentin Jabot via cfe-commits]

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@@ -17726,6 +17764,10 @@ static bool EvaluateAsStringImpl(Sema &SemaRef, Expr *Message,
 
   SourceLocation Loc = Message->getBeginLoc();
   QualType T = Message->getType().getNonReferenceType();
+  if (T->isPointerType() && T->getPointeeType()->isCharType())
+    return EvaluateAsNullTerminatedCharBuffer(
+        SemaRef, Message, Result, Ctx, EvalContext, ErrorOnInvalidMessage);
+
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cor3ntin wrote:

The problem of doing that here is that it is a non-standard behavior.
So at the minimum we'd need extension warnings. But I'm a bit uncomfortable adding that extension to begin with.

I think the functionality is best left to format string / ptrauth for now.

Which brings the question... how do we test this?


https://github.com/llvm/llvm-project/pull/173140