New comment by pullmoll on void-packages repository

https://github.com/void-linux/void-packages/pull/24424#issuecomment-678770482

Comment:
Bad news: trying to build gcc10-10.2.0 with isl 0.22.1 fails for several missing symbols,
so I don't think we should include this update with gcc too soon, unless someone wants
to take the time and try to deal with the (new) problems.

BTW we have `isl` and `isl15` where the latter is the newer version(s) since `isl-15.x` and the original `isl` is tracking the old version currently used only by `cloog`. The cross compilers and gcc use `isl15`.

Not sure what to do with this PR now and leaving it to other @void-linux/pkg-committers to decide.