Index: cmake/Modules/CompilerRTCompile.cmake
===================================================================
--- cmake/Modules/CompilerRTCompile.cmake
+++ cmake/Modules/CompilerRTCompile.cmake
@@ -136,7 +136,7 @@
       COMMAND bash -c "${CMD}"
       COMMENT "Checking that just-built clang can find C++ headers..."
       VERBATIM)
-    if (TARGET clang)
+    if (NOT COMPILER_RT_STANDALONE_BUILD)
       ADD_DEPENDENCIES(CompilerRTUnitTestCheckCxx clang)
     endif()
   endif()