https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82683
--- Comment #9 from Segher Boessenkool <segher at gcc dot gnu.org> --- The "failed to match" messages are hugely important (in fact, I want it to print more: _why_ did combination fail, in all the cases where it is not because of recog). The "deferring deletion" messages are not from combine (from df, instead). Yes they are annoying, much more so in other passes.