Regressions on native/master at commit r17-471 vs commit r17-464 on Linux/x86_64

[Haochen Jiang via Gcc-regression]

Regressions on master at commit r17-471 vs commit r17-464 on Linux/x86_64
New failures:

New passes:
FAIL: g++.dg/reflect/bases_of5.C  -std=c++26 (test for excess errors)