Is it impossible to use OpenMP in mex files with the only free C++ compiler that's compatible with MATLAB (Microsoft SDK 7.1)?

Really?

[Geoff Hayes]

John - are you observing an error when you try to compile the MEX file, and if so, what is it?

[John Billingham]

No error, but no multithreading.

Answer 1

[Jan]

Perhaps this helps: http://blog.codekills.net/2007/09/20/openmp-and-visual-c++-the-free-way-%28sorta%29/

[John Billingham]

Well, maybe, but I'm not sure I understand the answer. I'm no expert....and that's from 2007. Are you saying that fix still works for SDK 7.1?

[John Billingham]

If you look at the comments on the article you linked to, one of them points out that it doesn't work for current SDKs, and that was six years ago. :(

[Jan]

There is no official OMP support in the free MSVC Express versions. The article in the shown link explains how the OMP-libraries can be obtained by downloading tools available for free and some manual modifications. You did not specify which version of Matlab you are working with, but the linked page contains enough keywords for further searchs in the net.

So my answer is: Yes, it is possible, but not in a directly supported way. For productive work I would definitely prefer to buy a version of MSVC which supports OMP, because it is cheaper than experimenting for several hours.

[John Billingham]

It doesn't seem to be terribly widely known, but I've discovered that if you install Microsoft Visual Studio Community 2013, you get the latest C/C++ compiler available in MATLAB, with full OpenMP support. Infinitely more convenient than faffing around with a SDK.

[Jan]

@John: Which Matlab version does recognize this compiler?

[John Billingham]

2014b