Added -DPIC option on shared library.

Author: redboltz

CMakeLists.txt

@@ -146,7 +146,7 @@ IF (MSGPACK_BUILD_TESTS)
 ENDIF ()
 
 IF (CMAKE_COMPILER_IS_GNUCC)
-	SET_PROPERTY (TARGET msgpack APPEND_STRING PROPERTY COMPILE_FLAGS -Wall )
+	SET_PROPERTY (TARGET msgpack APPEND_STRING PROPERTY COMPILE_FLAGS "-Wall -DPIC")
 	SET_PROPERTY (TARGET msgpack-static APPEND_STRING PROPERTY COMPILE_FLAGS -Wall )
 ENDIF ()
 IF ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "MSVC")