[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.

> 
> clang driver needs a way to pick up aarch64-amazon-linux GCC installation. The user should specify `--gcc-triple=` correctly, or perhaps we can have a small hack within clang driver to do it.

We should not require the user to do anything more on AArch64 than they do on x86_64, and nothing more on Amazon Linux than they do on RedHat. That's consistency and neutrality.


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