Index: tools/llvm-config/CMakeLists.txt
===================================================================
--- tools/llvm-config/CMakeLists.txt
+++ tools/llvm-config/CMakeLists.txt
@@ -16,6 +16,11 @@
 set(LLVM_CPPFLAGS "${CMAKE_CPP_FLAGS} ${CMAKE_CPP_FLAGS_${uppercase_CMAKE_BUILD_TYPE}} ${LLVM_DEFINITIONS}")
 set(LLVM_CFLAGS "${CMAKE_C_FLAGS} ${CMAKE_C_FLAGS_${uppercase_CMAKE_BUILD_TYPE}} ${LLVM_DEFINITIONS}")
 set(LLVM_CXXFLAGS "${CMAKE_CXX_FLAGS} ${CMAKE_CXX_FLAGS_${uppercase_CMAKE_BUILD_TYPE}} ${LLVM_DEFINITIONS}")
+
+if (NOT LLVM_ENABLE_RTTI)
+  set(LLVM_CXXFLAGS "${LLVM_CXXFLAGS} -fno-rtti")
+endif()
+
 # Use the C++ link flags, since they should be a superset of C link flags.
 set(LLVM_LDFLAGS "${CMAKE_CXX_LINK_FLAGS}")
 set(LLVM_BUILDMODE ${CMAKE_BUILD_TYPE})