[llvm] [cmake] Serialize native builds for Make generator (PR #121021)

[via llvm-commits]

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@@ -9,7 +9,11 @@ function(llvm_ExternalProject_BuildCmd out_var target bin_dir)
   endif()
   if (CMAKE_GENERATOR MATCHES "Make")
     # Use special command for Makefiles to support parallelism.
-    set(${out_var} "$(MAKE)" "-C" "${bin_dir}" "${target}" PARENT_SCOPE)
+    set(make_cmd "$(MAKE)" "-C" "${bin_dir}" "${target}")
+    set(file_lock_script "${LLVM_CMAKE_DIR}/FileLock.cmake")
+    set(${out_var} ${CMAKE_COMMAND} "-DLOCK_FILE_PATH=${bin_dir}/cmake.lock"
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arthurqiu wrote:

Thanks for the suggestion! The extra stamp_dir argument is added.

https://github.com/llvm/llvm-project/pull/121021