For GDI version, it is better to build window application than to build console application, isn't it ?
Current GDI version is console application, so players cannot get error messages for assertion on nightly versions. It will quits immediately without any message.
SDI version can.
ifeq ($(OSTYPE),mingw)
CC ?= gcc
SOURCES += simsys_w32_png.cc
CFLAGS += -mno-cygwin -DPNG_STATIC -DZLIB_STATIC -march=pentium
ifeq ($(BACKEND),gdi)
LIBS += -lunicows
LDFLAGS += -mwindows
endif
LIBS += -lmingw32 -lgdi32 -lwinmm -lwsock32 -lz -lbz2
endif
I'm not sure this is the correct place to be.