Index: CMakeLists.txt
===================================================================
--- CMakeLists.txt
+++ CMakeLists.txt
@@ -9,7 +9,7 @@
 
 # Check if compiler-rt is built as a standalone project.
 if (CMAKE_SOURCE_DIR STREQUAL CMAKE_CURRENT_SOURCE_DIR)
-  project(CompilerRT C CXX)
+  project(CompilerRT C CXX ASM)
   set(COMPILER_RT_STANDALONE_BUILD TRUE)
 else()
   set(COMPILER_RT_STANDALONE_BUILD FALSE)
Index: lib/builtins/CMakeLists.txt
===================================================================
--- lib/builtins/CMakeLists.txt
+++ lib/builtins/CMakeLists.txt
@@ -274,7 +274,6 @@
         endif ()
       endforeach ()
 
-      set_source_files_properties(${${arch}_SOURCES} PROPERTIES LANGUAGE C)
       add_compiler_rt_runtime(clang_rt.builtins-${arch} ${arch} STATIC
                               SOURCES ${${arch}_SOURCES}
                               CFLAGS "-std=c99")