ASan on OSX Travis is incompatible with Rust's santiziers
In helping to debug https://trac.torproject.org/projects/tor/ticket/25386 I've found that an unfortunate case is being hit where
cargo test is using rustc's copy of the asan runtime instead of the system's copy, which causes problems due to presumably version mismatches between them.
The error looks like https://travis-ci.com/alexcrichton/tor/jobs/141409956 and only starts to show up after https://trac.torproject.org/projects/tor/ticket/27273 and https://trac.torproject.org/projects/tor/ticket/27272 are fixed.
AFAIK the only "fix" for this is to basically just delete the sanitizer runtimes in the Rust sysroot as they're not used anyway, but I'll try to keep thinking and see if there's a better solution!