Compilation error with Geant4 10.7 and/or gcc 4.8.5

[tkittel]

First half of this task is done in NCrystal v2.5.0 which has just been released, i.e. make sure NCrystal itself can be used in a multi-threaded application:

https://github.com/mctools/ncrystal/wiki/Announcement-Release2.5.0

The actual NCrystal-Geant4 hook still needs major work in order to benefit from this.

Hi @tkittel !

I am trying to install NCrystal to use with Geant4, but I am having some trouble that I don't understand. I'm hoping you might be able to shed some light on my issue.

When I build NCrystal with the G4Hook off, it works flawlessly and the post install test comes back successful; but when I try to build with the Geant4Hook on, I get an error in the ncrystal/ncrystal_geant4/src/G4NCProcWrapper file, as show in the first attached file. I have also attached the ccmake gui in case it's helpful.

Thanks so much!
Will

Originally posted by @Will-Kemmerer in #36 (comment)

[tkittel]

Hi @Will-Kemmerer,

Opening as a separate issue, as it is not really the same as #36. It seems there is a simple compilation error with Geant4 10.7 (I guess they either changed the meaning of G4int or enabled a stricter compilation flag).

I am now preparing a small release, v2.7.2, with this small fix for you. Note that as you can tell from #36, our Geant4 hooks are up for a major overhaul. But at least with this fix I was able to build against Geant4 10.7.p02 and run our small (single-threaded) ncrystal_example_g4sim example.

Cheers,
Thomas

[tkittel]

Actually, @Will-Kemmerer could you provide a bit more info about your system? There is one of the errors in your screen-dump that I can't reproduce on my system.

What platform? What compiler and version are you using? What flags did you use when you built Geant4 (specifically was it an MT build?).

[tkittel]

So I took a wild guess that you are on some older linux platform, for which a good bet is currently CentOS7 with gcc 4.8.5. Indeed, I was able to reproduce the compilation issues above, along with a few other ones.

I am preparing a new NCrystal release v2.7.2 now with the fixes. The code is already pushed to the develop branch of the ncrystal repo, so feel free to check it out already - and preferably report back here before the release in case you have additional issues :-)

Cheers,
Thomas

[Will-Kemmerer]

Hi @tkittel , I really appreciate your time and help with this. Sorry about the delay, I'm on US EST, so I just woke up.

In using:
Ubunutu 20.04.2 LTS
Cmake 3.20.5
GCC 9.3.0
Geant4-10.7.1.p01 (will be updating to p02)
Geant4 was built MT (Do I need to change this to work with Ncrystal when I update to p02?)

I am about to play around with the develop branch, and will update about any issues or lack of issues that come up!

Thanks so much,
Will

[Will-Kemmerer]

Dev branch compiled with G4 hook enabled! Post install test ran successfully

For anyone in the future, I updated to p02 and built G4 without MT

@tkittel Thanks again for the help :)

[tkittel]

Great, thanks for the feedback!

And for the record I think the MT build of Geant4 is likely OK, as long as you don't actually use it to launch a multi-threaded simulation (i.e. you must use the normal G4RunManager, not the MT version). And I think I actually ended up fixing a few compilation errors for Geant4 10.7 and some compilation errors for gcc 4.8.5...

Obviously it would be awesome if we had a better CI system set up which could systematically test all these combinations of versions of the various dependencies. Hopefully one day we will find the time :-)