Some VNL solvers are not thread-safe about itk HOT 20 OPEN

My guess is : vxl/vxl@3cdc40c

from itk.

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

from itk.

@nslay vxl has moved to github several years ago. Would you please reference the code on the github vxl site?

https://github.com/vxl/vxl

from itk.

Thanks for the prompt response!

I'm quite surprised because the github VXL repository has the same discrepancy as ITK while the sourceforge one is thread-safe. Here is the offending non-threadsafe lbfgsb.c code:

https://github.com/vxl/vxl/blob/master/v3p/netlib/opt/lbfgsb.c

I've downloaded the sourceforge one and attached it.

lbfgsb.txt

Sorry, github doesn't support C files. I renamed it with a .txt extension.

I wonder what happened in the migration to github!

from itk.

The very first commit on github is threadsafe. I'll try to find where it changed.
https://github.com/vxl/vxl/blob/ae9c7b5a9253f4ac14f5b247a816b5a1a559d80a/v3p/netlib/opt/lbfgsb.c

from itk.

The massive amount of static variables got reintroduced here (to fix another bug):
vxl/vxl@3cdc40c#diff-b59cc8496f016fff270b123014286c74

from itk.

I'm glad VXL is still alive and kicking! It's my favorite numerics library. I thought it was abandoned or was just extremely mature when I saw that the last commit was in 2013 on sourceforge.

Google pointed me to VXL's sourceforge (first result). Github wasn't anywhere in the search results!

from itk.

If somebody has write access to vxl.sourceforge.net, they could add a link to GitHub and state that VXL has moved there.

from itk.

I think that would be @bradking

from itk.

What I don't understand is why f2c emits static variables for otherwise local variables in the original Fortran code. I'd expect this for, say, Fortran's common blocks (yuck!), but not these variables!

Does Fortran have some sort of guarantee about the states of local variables in functions called multiple times?

from itk.

I've opened vxl/vxl#555 to discuss the future of the vxl homepage.

from itk.

@dzenanz FYI: vxl/vxl#555 . VXL homepage moved to github.

from itk.

@nslay f2c probably does not emit static, but f2c often produces a draft of code that subsequently requires modification in order to meet coding standards/ performance/linkage constraints not supported in the original implementation.

It would be fabulous if you could provide a pull request for this codebase that fixes the problem you identified.

both f2c, and the developers that attempted to fix this file are imperfect.

Thanks,
Hans

from itk.

Hi Hans,
ITK/VXL developers are not perfect!? I am outraged!

OK. I will work on this problem. I also apparently need to tidy up ITKIOOpenSlide!

Nate

from itk.

@nslay 👍 It was almost certainly me who made those static. Just be careful not to blindly move the old code forward. It may fix thread safety at the expense of re-introducing other problems.

Thanks for looking into this.

from itk.

hey, shouldn't this be reopened? Sounds like it's not fixed and people have told me it's still and issue. @hjmjohnson @thewtex

from itk.

Yeah yeah, I intended to fix this. I will have another look this weekend.

from itk.

@nslay THANK YOU!!!

You may want to look at recent upstream changes to this code base L-BFGS-B-C for fixing this+potentially other bugs. If you find additional bugs, perhaps we should submit them upstream.

from itk.

@nslay, ditto on @hjmjohnson's THANK YOU!!!

We have some code that can be used to help test when you are ready.

from itk.

This issue has been automatically marked as stale because it has not had recent activity. Thank you for your contributions.

from itk.