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Also a C99 type, I know we have 2012 and C99 sounds it should work everywhere this days, but I remember that last time I thought so (maybe 2-4 years ago) I still run into some platform where it caused trouble (don't remember anymore which one). Compiling certainly has to be fixed (but not by me as I can't test that platform).
Anyway, I'm moving this to bugreports, thanks for reporting.
This bug exist in a 32 or 64 bytes of compilation mode? I checked trunk with XCode 4.1 and it worked fine, but it looks like I will have to check it one more time. Thanks for report.
This is a weird type problem in the OpenGL specs. I think we might have to do some more ifdefs and mayv´be drop support for one of the extension methods.
I tried compiling in 64 bit mode with Xcode 4.3.3 (using clang 3.1). Sorry, should have added that information right from the beginning.
I see that the double cast is rather ugly and not really necessary, my mistake. Also I didn't realize that those C99 types still are an issue on some compilers.