OpenMP stable yet?

[Danack]

Hi,

I've just spent a few hours trying to figure out why ImageMagick was segfaulting in libgomp. Referencing this post from 2007 it seems that OpenMP crashing is a known issue.

Is there a version that is known to be stable on Centos 6.4, or a set of flags that need to be set to make it stable with OpenMP? Or should I just disable OpenMP when compiling ImageMagick?

cheers
Dan

[magick]

OpenMP support has been stable for years now. Your could try downloading ImageMagick 6.9.0, the current release and see if that helps. If you still get faults, try setting the MAGICK_THREAD_LIMIT environment variable to 2 and see if that makes a difference. If it still fails, disable OpenMP support in ImageMagick.

[Danack]

For reference then, using libgomp.x86_64 version 4.4.7-11.el6 on Centos when using ImageMagick 6.9.9.0 through Imagick has issues; namely it segfaults on exit in the libgomp library.

They may be caused by using OpenMP inside an application that is also managing its own threads.

So yeah, I'll just keep OpenMP disabled.

[fmw42]

Just curious if it is Imagick. Does it fail when using the terminal and command line or putting the command line in PHP exec()?

[Danack]

Hi fmw,

To be precise the segfault appeared I was testing with PHP cli and the segfault was being generated during the PHP shutdown phase.

Yes, it is almost certainly a problem caused by libgomp interacting either with just Imagick, or with some aspect of the PHP internal engine, but I don't have the tools/time to investigate that much further.

cheers
Dan