Index: lib/Basic/CMakeLists.txt
===================================================================
--- lib/Basic/CMakeLists.txt
+++ lib/Basic/CMakeLists.txt
@@ -12,7 +12,7 @@
 
 set(get_svn_script "${LLVM_CMAKE_PATH}/GetSVN.cmake")
 
-if(DEFINED llvm_vc AND DEFINED clang_vc)
+if(DEFINED llvm_vc AND DEFINED clang_vc AND LLVM_APPEND_VC_REV)
   # Create custom target to generate the VC revision include.
   add_custom_command(OUTPUT "${version_inc}"
     DEPENDS "${llvm_vc}" "${clang_vc}" "${get_svn_script}"