* Improve error message for new check on MinGW compiler version

CMakeLists.txt

@@ -235,11 +235,11 @@ ELSEIF ( "${CMAKE_CXX_COMPILER_ID}" MATCHES "Clang" )
   SET(CMAKE_C_FLAGS "-fPIC -fno-strict-aliasing ${CMAKE_C_FLAGS}")
 ELSEIF( CMAKE_COMPILER_IS_MINGW )
   IF (CMAKE_CXX_COMPILER_VERSION VERSION_LESS 7.0)
-    message(FATAL_ERROR "MinGW is too old")
+    message(FATAL_ERROR "MinGW is too old to be supported. Please update MinGW and try again.")
   ELSEIF(CMAKE_CXX_COMPILER_VERSION VERSION_LESS 7.3)
-    message(WARNING "MinGW is old, if you experience errors, update MinGW")
+    message(WARNING "MinGW is old, if you experience errors, update MinGW.")
   ENDIF()
-  SET( CMAKE_CXX_FLAGS "-fvisibility=hidden -fPIC -fno-strict-aliasing -Wall -Wno-long-long -std=c++11 -Wa,-mbig-obj ${CMAKE_CXX_FLAGS}" )
+  SET( CMAKE_CXX_FLAGS "-fvisibility=hidden -fno-strict-aliasing -Wall -Wno-long-long -std=c++11 -Wa,-mbig-obj ${CMAKE_CXX_FLAGS}" )
   SET(CMAKE_C_FLAGS "-fPIC -fno-strict-aliasing ${CMAKE_C_FLAGS} ")
   ADD_DEFINITIONS( -U__STRICT_ANSI__ )
 ENDIF()