rust-lang/rust — pull request #17083 by thestinger (2014-09-07 18:14:56+00:00)
Title: enable jemalloc debugging in unoptimized builds

The performance hit from these checks is significant, but unoptimized
builds are already incredibly slow. Enabling these checks results in
better test coverage since there are bots doing unoptimized builds, and
the cost is small in the context of an unoptimized build. This also
allows using `JEMALLOC_FLAGS` to override the default configure flags.