[clang] [llvm] Hurd: Add x86_64 support (PR #78065)

[Fangrui Song via cfe-commits]

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@@ -2652,6 +2652,31 @@ void Generic_GCC::GCCInstallationDetector::AddDefaultGCCPrefixes(
     return;
   }
 
+  if (TargetTriple.isOSHurd()) {
+    static const char *const X86_64HurdTriples[] = {"x86_64-gnu"};
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MaskRay wrote:

No. It's for `-m32`/`-m64`

https://github.com/llvm/llvm-project/pull/78065