[clang] [clang][Sema] Stop format size estimator upon %p to adapt to linux kernel's extension (PR #65969)

[Richard Smith via cfe-commits]

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@@ -1350,10 +1360,17 @@ void Sema::checkFortifiedBuiltinMemoryFunction(FunctionDecl *FD,
             llvm::APSInt::getUnsigned(H.getSizeLowerBound())
                 .extOrTrunc(SizeTypeWidth);
         if (FormatSize > *SourceSize && *SourceSize != 0) {
-          DiagID = diag::warn_fortify_source_format_truncation;
-          DestinationSize = SourceSize;
-          SourceSize = FormatSize;
-          break;
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zygoloid wrote:

This diagnostic used to override the production of the `warn_fortify_source_size_mismatch` warning, and now is produced in addition to it. Is that intentional?

https://github.com/llvm/llvm-project/pull/65969