https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85813
--- Comment #7 from Mathias Stearn <redbeard0531 at gmail dot com> --- > Simply returning an empty exception_ptr is what happened before the PR 64241 > change, so what we do now retains that behaviour. That might be the main > reason for it. Silently dropping errors always skeeves me out. I'm not sure if anyone is well served by the current behavior. If it were up to me (and I know it isn't) I'd make that case call std::terminate() or similar rather than returning the "no error" value. That seems consistent with the behavior of the __throw* functions, but it is a breaking change. Or even better, since gcc seems fine throwing through functions marked noexcept in -fno-exceptions TUs, maybe in the (very rare) case where copying/moving an exception throws inside an -fno-exceptions TU, just let it bubble out. > ::new (__e) _Ex(std::forward<_Ex>(__ex)); Should that be std::move(__ex)? I don't know why, but make_exception_ptr takes the exception by value rather than forwarding ref. I guess forward<_Ex> is fine either way, and will stay correct if that defect gets fixed. It just seemed odd to forward a value so I thought I'd mention it. > Mix-and-match works if the function gets inlined. Do you think this case warrants a [[gnu::always_inline]]? Given the sensitive nature of error handling, it seems pretty bad if a correct usage of make_exception_ptr() could be silently transformed to return the "no error" value just by linking in a bad library. Even if that library never dynamically executes make_exception_ptr(). I know I'd hate to be called in to debug that issue... I'm going to go make sure no code we link with uses -fno-exceptions!
