https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112737
--- Comment #10 from Hans-Peter Nilsson <hp at gcc dot gnu.org> --- Looks like this also fixed one of the remaining FAILs logged in PR112580, specifically "FAIL: g++.dg/modules/xtreme-header_b.C -std=c++2b (test for excess errors)".