[Bug libstdc++/81797] gcc 7.1.0 fails to build on macOS 10.13 (High Sierra):

[rlcamp.pdx at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81797

--- Comment #40 from Campbell <rlcamp.pdx at gmail dot com> ---
(In reply to Chris Johns from comment #38)
> FYI I do not see any build errors with the same version of MacOS on
> different hardware running HPFS. It is a different machine with a Fusion
> disk and that disk is not supported by APFS.

Yes, the problem is known to be specific to APFS, due to the finer resolution
of timestamps.

Why is .NOTPARALLEL not an acceptable solution, until a more thorough solution
is found? Is it actually possible to have an even reliably measurably longer
build time due to .NOTPARALLEL? It fixes the problem, albeit in an overly
conservative way. It would be much worse for it to continue to not work at all.