[libc] [llvm] [libc] Support multilib with runtimes build (PR #115357)

[Michael Jones via llvm-commits]

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@@ -635,6 +635,7 @@ if(build_runtimes)
           CMAKE_ARGS -DLLVM_DEFAULT_TARGET_TRIPLE=${name}
                      -DLLVM_RUNTIMES_PREFIX=${name}/
                      -DLLVM_RUNTIMES_LIBDIR_SUBDIR=${multilib}
+                     ${extra_cmake_args}
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michaelrj-google wrote:

is this related or is it debug code that snuck in?

https://github.com/llvm/llvm-project/pull/115357