https://gcc.gnu.org/bugzilla/show_bug.cgi?id=10837
--- Comment #17 from Lukas Grätz <lukas.gra...@tu-darmstadt.de> --- (In reply to Xi Ruoyao from comment #16) > (In reply to gooncreeper from comment #15) > > May I suggest we just add something like __attribute__((trace)) for the > > special abort case? Noreturn was added for code optimization after all, not > > for backtracing. > > It will break any attempts to debug an abort until the libc headers are > updated to use __attribute__((trace)). "any attempts"? We could simply use the gdb debugger and ignore the backtrace. In comparison, the backtrace is a rather restricted debugging instrument. If there are applications that really depend on GCC's backtrace, this should be the reason to keep the current behaviour. > > Note that in GCC noreturn has been added far before the WG14 _Noreturn paper > (even this ticket predates the WG14 paper), so the rationale in the paper > may not apply. Backtracing functionality is highly platform dependent, so there is no surprise that the C standard cannot guarantee anything about it. > > In practice most _Noreturn functions are abort, exit, ..., i.e. they are > only executed one time so optimizing against a cold path does not help much. > I don't think it's a good idea to encourage people to construct some fancy > code by a recursive _Noreturn function (why not just use a loop?!) ... and why not just if and goto? Because it is considered good programming practice to structure source code into functions (not to long) and loops. If a function gets too big, GCC might not optimize it well. > And if > you must write such fancy code anyway IMO musttail attribute (PR83324) will > be a better solution. I agree.
