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

[Fangrui Song via cfe-commits]

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@@ -78,3 +78,82 @@
 // CHECK-CROSS: "{{.*}}/Inputs/basic_cross_hurd_tree/usr/lib/gcc/i686-gnu/10/../../../../i686-gnu/bin/ld" {{.*}} "-m" "elf_i386"
 // CHECK-CROSS: "{{.*}}/Inputs/basic_cross_hurd_tree/usr/lib/gcc/i686-gnu/10/crtbegin.o"
 // CHECK-CROSS: "-L{{.*}}/Inputs/basic_cross_hurd_tree/usr/lib/gcc/i686-gnu/10/../../../../i686-gnu/lib"
+
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MaskRay wrote:

I have checked, but can you try another build with `-DCLANG_DEFAULT_RTLIB=compiler-rt -DCLANG_DEFAULT_UNWINDLIB=libunwind -DCLANG_DEFAULT_CXX_STDLIB=libc++` and see whether the test still passes?

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