When backporting the PR61414 fix to 8.4, I've noticed that the caching
of prec is actually broken, as it would fail to actually store the computed
precision into the hash_map's value and so next time we'd think the enum needs
0 bits.
2020-02-14 Jakub Jelinek <jakub@redhat.com>
PR c++/61414
* class.c (enum_min_precision): Change prec type from int to int &.
git://gcc.gnu.org / gcc.git / commit