diff --git a/CMakeLists.txt b/CMakeLists.txt
index 7a9b241..73fe07c 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -283,13 +283,6 @@ IF (MSGPACK_BUILD_TESTS)
     ADD_SUBDIRECTORY (test)
 ENDIF ()
 
-IF ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "Clang" OR "${CMAKE_CXX_COMPILER_ID}" STREQUAL "GNU")
-    IF (MSGPACK_ENABLE_SHARED)
-        SET_PROPERTY (TARGET msgpackc APPEND_STRING PROPERTY COMPILE_FLAGS "-Wall -Wextra -Werror -g -O3 -DPIC")
-    ENDIF ()
-    SET_PROPERTY (TARGET msgpackc-static APPEND_STRING PROPERTY COMPILE_FLAGS "-Wall -Wextra -Werror -g -O3" )
-ENDIF ()
-
 IF ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "Clang")
     SET_PROPERTY (TARGET msgpackc APPEND_STRING PROPERTY COMPILE_FLAGS " -Wno-mismatched-tags")
 ENDIF ()
diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index 5dfbbe4..5d1cb8a 100644
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -74,9 +74,6 @@ FOREACH (source_file ${check_PROGRAMS})
         ${CMAKE_THREAD_LIBS_INIT}
     )
     ADD_TEST (${source_file_we} ${source_file_we})
-    IF ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "Clang" OR "${CMAKE_CXX_COMPILER_ID}" STREQUAL "GNU")
-        SET_PROPERTY (TARGET ${source_file_we} APPEND_STRING PROPERTY COMPILE_FLAGS "-Wall -Wextra -Werror -g -O3 ")
-    ENDIF ()
     IF ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "Clang")
         SET_PROPERTY (TARGET ${source_file_we} APPEND_STRING PROPERTY COMPILE_FLAGS " -Wno-mismatched-tags")
     ENDIF ()