https://gcc.gnu.org/bugzilla/show_bug.cgi?id=120138
--- Comment #4 from Thor Preimesberger <tcpreimesberger at gmail dot com> --- FWIW I bisected to commit d45ddc2c04e471d0dcee016b6edacc00b8341b16 - adding this commit and compiling with -O3 causes two additional jumps to be threaded. The gimple stmt _68 = r[1] in transpose_avx512_contiguous_thin<float> is triggering uninit1. It looks like, before the above commit, the above gimple has a couple more nodes that are visited by walk_aliased_vdefs in maybe_warn_operand. I have some nasty printf debugging logs but I'm not sure if they're useful enough to bother attaching
