https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97717
Richard Biener <rguenth at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Ever confirmed|0 |1 Status|UNCONFIRMED |WAITING Last reconfirmed| |2020-11-05 --- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> --- What's the stack limit for processes under WSL-2? Try ulimit -s unlimited. Otherwise it's hard to say what goes wrong without a backtrace, I can't reproduce on x86_64-linux. But the testcase complains about uses of 'auto' and suggests -fconcepts (which doesn't mitigate them). Are you really using plain -O3?