I tried plan9port's mk for a moment out of curiosity. I quickly ran into an annoying usability problem: it compares file mtimes with second accuracy. https://g

I tried plan9port's mk for a moment out of curiosity. I quickly ran into an annoying usability problem: it compares file mtimes with second accuracy. https://github.com/9fans/plan9port/blob/cc4571fec67407652b03d6603ada6580de2194dc/src/cmd/mk/unix.c#L346 https://github.com/9fans/plan9port/blob/cc4571fec67407652b03... With sub-second build times for individual targets, this causes mk to needlessly recompile files because the target may have the same mtime as the prerequisites.