[clang] [WIP][clang] Fix std::tm etc. mangling on Solaris (PR #106353)

[Rainer Orth via cfe-commits]

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@@ -1604,10 +1604,12 @@ static bool isTargetVariantEnvironment(const TargetInfo &TI,
   return false;
 }
 
-#if defined(__sun__) && defined(__svr4__)
+#if defined(__sun__) && defined(__svr4__) && defined(__clang__) &&             \
+    __clang__ < 20
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rorth wrote:

Certainly: the fix for GCC PR libstdc++-v3/1773 went in 13 years ago.  That should be good enough ;-)

https://github.com/llvm/llvm-project/pull/106353