OpenGL header problems

Harold L Hunt II
Mon Mar 1 05:34:00 GMT 2004

As I mentioned in my email about enabling indirect OpenGL acceleration, 
there are some problems when trying to link to -lopengl32.

I tracked this down to problems with the way that 
/usr/include/w32api/GL/gl.h decorates the function declarations for the 
gl* functions.  There are some collisions between the way that the 
standard windows headers define WINGDIAPI and APIENTRY and the way that 
gl.h expects them to be.

However, the problem is a little trickier than just that: I added a call 
to glPixelStorei in Xserver/hw/xwin/InitOutput.c (without #including any 
opengl headers) and instead made my own prototype for glPixelStorei.  If 
I made it:

void __stdcall glPixelStorei (unsigned int, int);

then the linker would complain about how it had to fixup a reference to 
glPixelStorei as _glPixelStorei@8.  But that is exactly what the 
__stdcall was supposed to do, so I am getting a little confused about 
why the prototype was being ignored.

I need an expert on __stdcall and w32api headers to give me a hand here. 
  Igor, I saw a post you made on this subject before, so I am counting 
on you :)

Once this little trick is solved we will have to figure out how to get 
the proper headers in exports/include/GL/; that directory currently 
getes some Mesa headers in it.  I'm not sure if we can cleanly disable 
that and point to the w32api OpenGL headers instead.


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