Fix MinGW build for Ninja generator

Author: kmilos

cmake/compilerFlags.cmake

@@ -41,7 +41,7 @@ if ( MINGW OR UNIX OR MSYS ) # MINGW, Linux, APPLE, CYGWIN
 
         add_compile_options(-Wp,-D_GLIBCXX_ASSERTIONS)
 
-        if (CMAKE_BUILD_TYPE STREQUAL Release AND NOT APPLE AND NOT MSYS)
+        if (CMAKE_BUILD_TYPE STREQUAL Release AND NOT (APPLE OR MINGW OR MSYS))
             add_compile_options(-Wp,-D_FORTIFY_SOURCE=2) # Requires to compile with -O2
         endif()