Index: runtimes/CMakeLists.txt
===================================================================
--- runtimes/CMakeLists.txt
+++ runtimes/CMakeLists.txt
@@ -122,7 +122,8 @@
   # before the just-built compiler can pass the configuration tests.
   if(EXISTS ${CMAKE_CURRENT_SOURCE_DIR}/compiler-rt)
     llvm_ExternalProject_Add(builtins
-                             ${CMAKE_CURRENT_SOURCE_DIR}/compiler-rt/lib/builtins
+                             ${CMAKE_CURRENT_SOURCE_DIR}
+                             CMAKE_ARGS -DCOMPILER_RT_BUILD_SANITIZERS=Off
                              PASSTHROUGH_PREFIXES COMPILER_RT
                              USE_TOOLCHAIN)
     set(deps builtins)