julia

3b51323f - Evaluate Circle CI (23171 but from a branch in JuliaLang) (#23188)

Evaluate Circle CI (23171 but from a branch in JuliaLang) (#23188) This runs in circleci's python 2.7 docker image which is based on debian jessie, mostly for convenience since that image has a non-root user added and some of the Julia tests work differently when run as root. Circle CI caching is a little odd - I'm using ccache here since it's actually fast enough to handle it pretty well, about 15 minutes to build deps from scratch and about 3 minutes to build deps with a primed ccache. We save the ARCH, HOME (default location where ccache saves its data, in case we switch containers and try to run tests as a different user), and year and week number into a tag file, then determine which saved circleci cache tag to load from based on the checksum of that tag file. So this will throw out the cache and have to rebuild it once a week, but since that only adds about 10-15 minutes to a build that's not a big deal. It would be better if circle's cache worked like Travis and AppVeyor's where it loads the latest and checksums the content to decide whether to upload a new replacement cache, but that's up to circle to fix. This has to skip the socket tests, since circle doesn't currently support ipv6 in their docker workers. They have other types of workers, but they aren't anywhere near as fast to build or run tests. This currently doesn't do a doc build or deployment, that's a TODO if we decide to switch to this. It also looks like it checks out the branch tip instead of the merge commit, but that should be fixable. Here I've set JULIA_CPU_CORES to 6 - in some testing on my fork this was a few minutes faster, but may run a higher risk of getting OOM killed. The merge commit is checked out manually due to Circle limitations.