https://gcc.gnu.org/bugzilla/show_bug.cgi?id=121159
--- Comment #23 from Lukas Grätz <lukas.gra...@tu-darmstadt.de> --- (In reply to Eric Botcazou from comment #22) > > I must say I'm not sure how musttail calls work at all on SPARC at -O0. > > The thing is sparc_function_ok_for_sibcall depends on flag_delayed_branch > > and that is only enabled by default for -O1 and higher. > > Perhaps we need to enable some subset of delayed branch processing in > > cfun->has_musttail functions even if !flag_delayed_branch? > > -fno-delayed-branch should prevail though, either implicitly or explicitly, > so the error at -O0 is OK in my opinion. At least from a user's perspective, that error is not Ok. It does not say "-fdelayed-branch is needed," it says "target is not able..." Also, it is important for debugging that code compiled with -O_ is also able to compile with -O0.
