Sorry for not describing my problem more clearly. This error happens without even
Here's a little more detail:
Using CUDA 3.0 Beta, Python 2.6, Mac OS X 10.6:
1. Python running in 32 bit mode, Boost & PyCUDA compiled for 32-bit architecture
=> no problems.
2. (Default on OS X 10.6) Python running in 64 bit mode, Boost & PyCUDA compiled for
64-bit architecture => the following error
import pycuda._driver # dynamically loaded from
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "/tmp/pycuda/build/lib.macosx-10.6-i386-2.6/pycuda/autoinit.py", line 4,
pycuda._driver.LogicError: cuInit failed: pointer is 64-bit
It's not a super big problem right now, since I can just force 32-bit mode when I
build everything, but since everything on OS X 10.6 is 64-bit by default, it's a
little extra snag for new people to have to compile everything differently, and remember
to set a special environment variable (VERSIONER_PYTHON_PREFER_32_BIT=yes) to get Python
to run in 32-bit mode.
Or maybe there's a quirk of my own particular installation that's causing this and
it's not going to be a problem for anyone else... ;)
On Nov 23, 2009, at 8:31 PM, Andreas Klöckner wrote:
On Montag 23 November 2009, Bryan Catanzaro wrote:
I built 64-bit versions of Boost and PyCUDA on
Mac OS X Snow Leopard, as
well as the 64-bit Python interpreter supplied by Apple, as well as the
CUDA 3.0 beta. Everything built fine, but when I ran pycuda.autoinit, I
got an interesting CUDA error, which PyCUDA reported as "pointer is
64-bit". I'm wondering - is it impossible to use a 64-bit host program
with a 32-bit GPU program under CUDA 3.0?
First, I'm not sure I fully understand what's going on. You can indeed compile
GPU code to match a 32-bit ABI on a 64-bit machine (nvcc --machine 32 ...). Is
that what you're doing? If so, why? (Normally, nvcc will default to your
host's ABI. By and large, this changes struct alignment rules and pointer
If you're not doing anything special to get 32-bit GPU code, then your GPU
code should end up matching your host ABI. Or maybe nvcc draws the wrong
conclusions or is a fat binary or something and we need to actually specify
the --machine flag.
I also remember wondering what the error message referred to when I added it.
I'm totally not sure. Which routine throws it?
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