On Fri, Oct 13, 2017 at 10:25:10AM -0400, Derrick Stolee wrote: > This does appear to be the problem. The missing DIFF_OPT_HAS_CHANGES is > causing diff_can_quit_early() to return false. Due to the corner-case of the > bug it seems it will not be a huge performance improvement in most cases. > Still worth fixing and I'm looking at your suggestions to try and learn this > area better. Yeah, I just timed some pathspec limits on linux.git, and it makes at best a fraction of a percent improvement (but any improvement is well within run-to-run noise). Which is not surprising. I agree it's worth fixing, though. -Peff