[Bug c++/107351] Bootstrap fails when gcc is built with gcc-13-master: error: conversion from 'long unsigned int' to 'unsigned int' changes value from '7001010000' to '2706042704'

[slyfox at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107351

--- Comment #4 from Sergei Trofimovich <slyfox at gcc dot gnu.org> ---
Attached the build log.

I completely forgot about the fact that I was using gcc source from
"normalized" filesystem which intentionally resets all timestamps (it's one of
the build modes for my distribution to validate build determinism):

$ LANG=C ls -l
/nix/store/p2m8xz3klafr1ydbjf8g86vmylziscr3-source/gcc/cp/module.cc
-r--r--r-- 4 root root 533735 Jan  1  1970
/nix/store/p2m8xz3klafr1ydbjf8g86vmylziscr3-source/gcc/cp/module.cc

Silly question: would it be reasonable for module.cc to use
gcc/{BASE-VER,DATESTAMP}?