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

[howarth.at.gcc at gmail dot com]

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

--- Comment #11 from Jack Howarth <howarth.at.gcc at gmail dot com> ---
(In reply to Francois-Xavier Coudert from comment #10)
> (In reply to Jack Howarth from comment #9)
> 
> 
> The only thing I can think of is that maybe, just maybe, it's due to
> filesystem timestamp granularity? My 10.13 system is running on APFS
> filesystem, which has 1 ns granularity (smaller than 1 s for HFS+).

That sounds much more likely as the trigger for the problem. I only have hard
drives to test 10.13 on so I am stuck with HFS (and wouldn't press the envelope
with APFS without using it on an SSD).