Recommended version of gcc?

(Heather999) #1

Is there a recommended version of gcc to use when installing from source? I see CentOS7 is still listed as the reference platform. I ask since we found with PhoSim, the development team is using gcc 5.2.0 and it made a difference in terms of performance at NERSC.

(Jim Bosch) #2

All of our CI systems use gcc 4.8, I believe, but many of us are using gcc 5.x or gcc 6.x on our development systems (I’m running 5.4). I’m not sure if anyone is running on 7.x. As far as I know, the stack itself works fine on all those and we’d consider a failure to work with one of them a high-priority bug.

However, there have been problems with using gcc 5+ with using Anaconda (see DM-10343) and OpenMP (which we do not use ourselves, at least not yet), and in fact that’s been a big blocker for us moving to a newer gcc as our minimum compiler. That’s basically because Anaconda provides binaries that were compiled with a much older gcc. Before doing an Anaconda-based install on gcc 5+ on a big system, it’d be good to read through that issue and understand what might go wrong.

(Heather999) #3

ok that helps! I’ve been using gcc 4.9.3, as I saw no reason to use a newer gcc at NERSC and we do use Anaconda (at least with some of our builds). It sounds as though that’s fine at the moment. Thank you!

(Pim Schellart) #4

Please also note DM-10902.
If and when that is solved we hope to be using devtoolset-6 (i.e. GCC 6.2.1) on our development systems (and that may become the recommended default).