https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95111
--- Comment #17 from Ville Voutilainen <ville.voutilainen at gmail dot com> --- (In reply to Ville Voutilainen from comment #16) > (In reply to Iain Sandoe from comment #14) > > (In reply to Ville Voutilainen from comment #12) > > The idea of bringing the lambda's captures into the coro frame was what I > > originally implemented. Richard pointed out that this is wrong when the > > lambda is mutable (see > > gcc/testsuite/g++.dg/coroutines/torture/lambda-10-mutable.C) > > > > so if one has > > > > auto X = [...] () -> some_coro<xxx> {}; > > > > X must exist for the duration of the lambda coro [it was pointed out by > > Lewis that really this is only the same as saying that if you have a class > > with a member function lambda, the instance of that class has to persist for > > the duration of the coro]. > > Ah. So the work-around for this problem is to copy the capture to a local > variable, and co_return that; then the local variable is in the coro-state. > Right? That is, instead of writing [x] {co_return x;} write [x] {auto xx = x; co_return xx;}