https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100850
Bug ID: 100850 Summary: [coroutine] Wrong addresses of variables captured by reference into lambda co-routines. Product: gcc Version: 11.1.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c++ Assignee: unassigned at gcc dot gnu.org Reporter: vsolontsov at volanttrading dot com Target Milestone: --- In a code like this: ``` int i; auto coro = [&i, pi = &i](int& i1) -> task { // co_await std::suspend_always{}; std::cout << "&i==&i1: " << std::boolalpha << (&i == &i1) << std::endl; std::cout << "&i==pi: " << std::boolalpha << (&i == pi) << std::endl; std::cout << "&i1==pi: " << std::boolalpha << (&i1 == pi) << std::endl; co_return; }(i); ``` If the captured variables are not used until the very first suspension, the addresses appear to be wrong. https://godbolt.org/z/c945q893j If the `task::initial_suspend()` returns `suspend_never` and the `co_await` in the co-routine is commented out, all good. Otherwise, if there's a suspension before the first use of the variables, the address get screwed.