diff --git a/CMakeLists.txt b/CMakeLists.txt
index 4f3806108..ecb166661 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -102,8 +102,6 @@ else()
     set(MINGW_FLAG "${MINGW_FLAG} -DWIN32_LEAN_AND_MEAN")
     set(Boost_THREADAPI win32)
     include_directories(SYSTEM src/platform/mingw)
-  else()
-    set(MINGW_FLAG "")
   endif()
   set(C_WARNINGS "-Waggregate-return -Wnested-externs -Wold-style-definition -Wstrict-prototypes")
   set(CXX_WARNINGS "-Wno-reorder -Wno-missing-field-initializers")