Index: cmake/modules/HandleLLVMOptions.cmake
===================================================================
--- cmake/modules/HandleLLVMOptions.cmake
+++ cmake/modules/HandleLLVMOptions.cmake
@@ -401,6 +401,9 @@
   else()
     message(WARNING "LLVM_USE_SANITIZER is not supported on this platform.")
   endif()
+  if (LLVM_USE_SANITIZE_COVERAGE)
+    append("-fsanitize-coverage=3" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
+  endif()
 endif()
 
 # Turn on -gsplit-dwarf if requested