Re: Intermittent parallel make rebuild failures

[Edward Welbourne]

> it appears from running make with the debug option that the
> top level make does not see the object file created by the lower level
> make in the time when it checks the dependencies for the library.

sounds a *lot* like an issue with make's caching of stat information;
if the uppper make has looked, before the lower makes them, for files
the lower makes, then its cached information about these files is
still in place telling it they're missing even after the lower has
made them.

That this only happens in parallel builds suggests that, while the
lower make is at work, the upper is attempting to get on with things
that actually depend on the lower.  So you may find that making
completion of the lower a prerequisite of the rules that are being
broken will help.

        Eddy.