https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97284
--- Comment #10 from Ville Voutilainen <ville.voutilainen at gmail dot com> --- Right - that's the Qt bug I'm hoping to fix, but I don't get far because of the ICE. :) The libstdc++ headers have been reorganized, so Qt's expectations that numeric_limits is available without including <limits> are no longer valid with GCC 11.