Update to 9.x

[timsnyder]

@isuruf and @beckermr, My team is hitting a bug in GCC 7.3 on linux and we'd like to see conda-forge update to something that has it fixed. I see that you have some work in progress on the https://github.com/conda-forge/ctng-compilers-feedstock/tree/libgcc-and-libstdcxx-9 branch to get things updated to 9.2.

What's left to be done there? I don't see gcc 9.x packages on anaconda.org yet. Perhaps I'm looking in the wrong place. Could I or someone on my team help push it the rest of the way?

[isuruf]

That's just for libgcc and libstdcxx. To get a full gcc build, we need to update https://github.com/conda-forge/crosstool-ng-feedstock/blob/master/recipe/meta.yaml to a recent version of crosstool-ng and port the patches in the continuum org's fork of crosstool-ng.

[beckermr]

We'd also want to bump gfortran on osx at the same time.

[beckermr]

@timsnyder If you want to work on this, lots of help is welcome!

[timsnyder]

OK. @bdutro-sv is working on this with me.

[timsnyder]

@mingwandroid, any chance you've looked at updating crosstool-ng that we should leverage?

[beckermr]

cc @brianv0 for viz

Also see this documentation: https://conda-forge.org/docs/maintainer/infrastructure.html#compilers-and-runtimes

I think we are acting in a way that is consistent with our stated principles. ;)

This will be the comp9 stack. One issue is how much we want to break environments with defaults. I forget the exact details, but I think the gfortran changes will need rebuilds, but not the other ones?

[bdutro-sv]

@beckermr it looks like crosstool-ng dropped support for OS X: https://crosstool-ng.github.io/2019/04/13/release-1.24.0.html

[beckermr]

We do not use crosstool-ng on osx.

We keep separate builds of just gfortran here since we don't need all of gcc

https://github.com/conda-forge/gfortran_osx-64-feedstock https://github.com/conda-forge/gfortran_impl_osx-64-feedstock

These need to be updated to 9 or 7.5 or w/e.