diff --git a/clang/cmake/modules/CMakeLists.txt b/clang/cmake/modules/CMakeLists.txt
--- a/clang/cmake/modules/CMakeLists.txt
+++ b/clang/cmake/modules/CMakeLists.txt
@@ -28,6 +28,14 @@
 set(CLANG_CONFIG_CMAKE_DIR)
 set(CLANG_CONFIG_LLVM_CMAKE_DIR)
 
+# For compatibility with projects that include(ClangConfig)
+# via CMAKE_MODULE_PATH, place API modules next to it.
+file(COPY .
+  DESTINATION ${clang_cmake_builddir}
+  FILES_MATCHING PATTERN *.cmake
+  PATTERN CMakeFiles EXCLUDE
+  )
+
 # Generate ClangConfig.cmake for the install tree.
 set(CLANG_CONFIG_CODE "
 # Compute the installation prefix from this LLVMConfig.cmake file location.