[compiler-rt] [llvm] [compiler-rt] Add check-builtins target for LLVM_ENABLE_RUNTIMES builds (PR #166837)

[Petr Hosek via llvm-commits]

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@@ -1028,6 +1025,7 @@ else ()
                               C_STANDARD 11
                               CXX_STANDARD 17
                               PARENT_TARGET builtins)
+      file(WRITE "${CMAKE_BINARY_DIR}/clang_rt.builtins-${arch}.sources.txt" "${${arch}_SOURCES}")
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petrhosek wrote:

Can you add a comment explaining what this is used for?

https://github.com/llvm/llvm-project/pull/166837