diff --git a/CMakeLists.txt b/CMakeLists.txt
index ceda71b..efb259e 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -50,7 +50,6 @@ if(CCACHE_FOUND)
 endif(CCACHE_FOUND)
 
 if ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "GNU")
-    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -march=native -Wall -Wextra -Werror")
     if (RAPIDJSON_BUILD_CXX11)
         if (CMAKE_CXX_COMPILER_VERSION VERSION_LESS "4.7.0")
             set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++0x")
@@ -73,7 +72,6 @@ if ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "GNU")
         endif()
     endif()
 elseif (CMAKE_CXX_COMPILER_ID MATCHES "Clang")
-    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -march=native -Wall -Wextra -Werror -Wno-missing-field-initializers")
     if (RAPIDJSON_BUILD_CXX11)
         set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11")
     endif()
@@ -88,7 +86,6 @@ elseif (CMAKE_CXX_COMPILER_ID MATCHES "Clang")
         endif()
     endif()
 elseif ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "MSVC")
-    add_definitions(-D_CRT_SECURE_NO_WARNINGS=1)
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} /EHsc")
 endif()