--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -53,8 +53,6 @@ if(CMAKE_CXX_COMPILER_ID STREQUAL "MSVC")
   add_definitions(-D_HAS_EXCEPTIONS=0)
 
   # Disable RTTI.
-  string(REGEX REPLACE "/GR" "" CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS}")
-  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} /GR-")
 else(CMAKE_CXX_COMPILER_ID STREQUAL "MSVC")
   # Use -Wall for clang and gcc.
   if(NOT CMAKE_CXX_FLAGS MATCHES "-Wall")
@@ -78,8 +76,6 @@ endif()
   set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fno-exceptions")
 
   # Disable RTTI.
-  string(REGEX REPLACE "-frtti" "" CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS}")
-  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fno-rtti")
 endif(CMAKE_CXX_COMPILER_ID STREQUAL "MSVC")
 
 # BUILD_SHARED_LIBS is a standard CMake variable, but we declare it here to make
