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

[Fangrui Song 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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MaskRay wrote:

`llvm/cmake/config.guess` has diverged from GCC. I vaguely recall that we did not sync it because llvm-project doesn't like the newer GPL 3 version.

It's not a dangerous precedence for Amazon to change this. I've tried two musl-based Linux distros and both require the user to explicitly specify linux-musl . I see that Amazon users want convenience and do not want to specify LLVM_DEFAULT_TARGET_TRIPLE, then it's your responsibility to update config.guess.

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