https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95137
--- Comment #43 from niek <niekb at scintilla dot utwente.nl> --- (In reply to Rafael Avila de Espindola from comment #29) > Created attachment 48771 [details] > Testcase without lambda coroutines > > I modified the testcase to also build with clang and not depend on async > lambdas. This still reproduces the problem with gcc with undefined behaviour > sanitizer, but works with with clang and sanitizers and gcc with valgrind. Hi Rafael, I tried your testcase on GCC trunk today (2021-09-28), and the testcase now seems to pass (!), even with asan and ubsan enabled. I tested with Compiler Explorer, with options -std=c++20 -g -fcoroutines -fsanitize=address,undefined and with the "compile to binary" and "execute the code" options. The only thing is that I had to include the <utility> header; gcc was complaining about not finding std::exchange. Does this mean (and could you please reconfirm) that bug 95317 has disappeared in trunk (which will become GCC 12)?