diff --git a/config.mk b/config.mk
index 64a1da9..5059632 100644
--- a/config.mk
+++ b/config.mk
@@ -21,8 +21,8 @@ LIBS = -L$(X11LIB) -lm -lrt -lX11 -lutil -lXft \
        `$(PKG_CONFIG) --libs freetype2`
 
 # flags
-CPPFLAGS = -DVERSION=\"$(VERSION)\" -D_XOPEN_SOURCE=600
-STCFLAGS = $(INCS) $(CPPFLAGS) $(CFLAGS)
+STCPPFLAGS = -DVERSION=\"$(VERSION)\" -D_XOPEN_SOURCE=600
+STCFLAGS = $(INCS) $(STCPPFLAGS) $(CPPFLAGS) $(CFLAGS)
 STLDFLAGS = $(LIBS) $(LDFLAGS)
 
 # OpenBSD: