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mfort
12-17-2009, 08:55 AM
FYI I've found very obscure bug in NVIDIA drivers.
It only applies for Win x64 with native x64 exe.
Tested drivers up to 195.62

wglMakeCurrent crashes when you allocate 2GB by small chunks before. If you allocate one big chunk of memory, then wglMakeCurrent works well.

It looks like the driver simply allocates some memory. When the pointer is > 2GB then it fails (probably casting to 32bit integer).

The reason why it does not fail when allocating 2GB in one call is that there is simple enough small free blocks at address < 2GB that can be used for driver allocation.

ATI drivers are OK.

100 lines C++ repro case available on request.

Are there any ways to force NV to fix it?

barthold
12-17-2009, 12:46 PM
> Are there any ways to force NV to fix it?

No :-) But if you email me your repro case, we'll take a look.

Barthold
(with my NVIDIA hat on)

mfort
12-17-2009, 01:12 PM
Email sent, thank you!

mfort
01-13-2010, 01:38 PM
SOLVED!

I'd like to thank Barthold Lichtenbelt and NVIDIA driver team to find and fix the problem.