[clang] [clang][bytecode] Reapply "Use tailcalls via `[[clang::musttail]]`" (PR #188419)

[Lukas Sommer via cfe-commits]

Timm =?utf-8?q?Bäder?= <tbaeder at redhat.com>,
Timm =?utf-8?q?Bäder?= <tbaeder at redhat.com>
Message-ID:
In-Reply-To: <llvm.org/llvm/llvm-project/pull/188419 at github.com>


sommerlukas wrote:

> Yeah, that should be `__has_feature`.

Yes, that works:
```diff
diff --git a/clang/lib/AST/ByteCode/Interp.h b/clang/lib/AST/ByteCode/Interp.h
index 3578ef9da820..41a9cf371947 100644
--- a/clang/lib/AST/ByteCode/Interp.h
+++ b/clang/lib/AST/ByteCode/Interp.h
@@ -38,7 +38,9 @@

 // preserve_none is supported on aarch64, but causes problems when asan is
 // enabled. See https://github.com/llvm/llvm-project/issues/177519.
+// preserve_none also causes problems on clang <= 19 if asan is enabled.
 #if !defined(__aarch64__) && !defined(__i386__) &&                             \
+    !(defined(__clang_major__) && __clang_major__ <= 19 && __has_feature(address_sanitizer)) && \
     __has_cpp_attribute(clang::preserve_none)
 #define PRESERVE_NONE [[clang::preserve_none]]
 #else
```

https://github.com/llvm/llvm-project/pull/188419