[CMake] Speculative fix for linker error on Linux

I can't reproduce this locally, but I think this may fix it.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@259870 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/CMakeLists.txt b/CMakeLists.txt
index d7a498d12819dfcfb13bb4e122a97a5920c051e3..514cea16ff9eb8d92ab4b76603a22327dfa2b8e3 100644 (file)
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -595,8 +595,8 @@ endif()
 set(CLANG_ORDER_FILE ${CMAKE_CURRENT_BINARY_DIR}/clang.order CACHE FILEPATH
   "Order file to use when compiling clang in order to improve startup time.")
 
-if(NOT EXISTS ${CLANG_ORDER_FILE})
-  execute_process(COMMAND ${CMAKE_COMMAND} -E touch ${CLANG_ORDER_FILE})
+if(CLANG_ORDER_FILE AND NOT EXISTS ${CLANG_ORDER_FILE})
+  file(WRITE ${CLANG_ORDER_FILE} "\n")
 endif()
 
 if (CLANG_BUILT_STANDALONE OR CMAKE_VERSION VERSION_EQUAL 3 OR