-SDL_CFLAGS := -DUSE_SDL_LIBRARY $(shell sdl-config --cflags)
-SDL_LDFLAGS := $(SDL_EXTRA_LIBS) $(shell sdl-config --libs)
-
-X11_CFLAGS = -DUSE_X11_LIBRARY $(X11_INCL)
-X11_LDFLAGS = $(X11_LIBS) -lX11
-
-ifeq ($(USE_SDL),true)
-SYS_CFLAGS = $(SDL_CFLAGS)
-SYS_LDFLAGS = $(SDL_LDFLAGS)
-else
-SYS_CFLAGS = $(X11_CFLAGS)
-SYS_LDFLAGS = $(X11_LDFLAGS)
-endif
-
-INCL = $(SYS_CFLAGS)
-LIBS = $(SYS_LDFLAGS) $(EXTRA_LIBS) -lm
-
-endif # (PLATFORM != dos)