Ok, so I will try with 0.5.3 this time.
I am a bit surprised when I am reading what I have done myself when I wrote the MinGW-32 building guide. I simply don't understand how it can work.
Set up SDL_gfx
LIBS = -L..\SDL-1.2.15\lib -lSDL
This should mean I was statically linking to SDL when building SDL_gfx.dll, right?
Build and run OpenXcom
LDFLAGS=(...) \bin\SDL.dll (...) ..\SDL_gfx-2.0.2\bin\SDL_gfx.dll (...) -mwindows
This should mean I link dynamically to both SDL.dll and SDL_gfx.dll...
So, why the hell did this work? Shouldn't I have SDL external functions defined both in SDL.dll and SDL_gfx.dll?
If anybody has built SDL_gfx by himself, could he tell me if he linked to SDL statically or dynamically?
Edit: I checked the two dlls in my 3 years untouched 32-bit building directories, SDL_gfx.dll is way smaller than SDL.dll, it's impossible SDL_gfx.dll contains all SDL.dll functions. I wonder what's happening exactly...