[llvm] [TargetParser] Parse Amazon Linux triple and handle RuntimeLibcalls (PR #136114)

[Paul Osmialowski via llvm-commits]

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@@ -173,7 +173,7 @@ void RuntimeLibcallsInfo::initLibcalls(const Triple &TT) {
     setLibcallName(RTLIB::EXP10_F64, "__exp10");
   }
 
-  if (TT.isGNUEnvironment() || TT.isOSFuchsia() ||
+  if (TT.isGNUEnvironment() || TT.isOSFuchsia() || TT.isAmazonLinux() ||
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pawosm-arm wrote:

> > Perhaps we need a llvm/cmake/config.guess change.
> 
> Yes, that's one way we could explore, perhaps after restoring LLVM's consistency (and neutrality). This can happen in parallel, meanwhile we'd have to propose something that would fit into the LLVM21 timeframe.

I looked into `llvm/cmake/config.guess`, there is nothing about any other Linux distro (Ubuntu, RedHat, Suse, Gentoo), so special treatment for any specific distro like Amazon would create a dangerous precedence. Also diverging even more from the upstream config.guess is not good. And config.guess upstream will never accept a change like that.

https://github.com/llvm/llvm-project/pull/136114