> link with gdi32 as well:  -lgdi32
>
> Look at the Makefile for a full list of required dll's

If it was me, I'd worry a bit about the lib order as well... mingw is a gcc, so is sensitive to linking order. You really want to ensure that any lib using a function is listed before the lib the provides it, so

-lACE -lfltk_forms -lfltk_gl -lfltk_images -lfltk -ldgi32 -lws2_32 -lmswsock -lwsock32 -lnetapi32 -lopengl32

might be a better option...

As a quick check, running fltk-config --use-forms --use-images --use-gl --ldflags on my machine lists...

 fltk-config --use-forms --use-images --use-gl --ldflags
-L/usr/local/lib -mwindows -mno-cygwin -lfltk_images -lfltk_png -lfltk_z -lfltk_jpeg -lfltk_gl -lglu32 -lopengl32 -lfltk_forms -lfltk -lole32 -luuid -lcomctl32 -lwsock32

Any use?


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