[Bug middle-end/56727] Recursive call goes through the PLT unnecessarily

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=56727

--- Comment #10 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
(In reply to Yuri Gribov from comment #9)
> (In reply to Alexander Monakov from comment #8)
> > Well, if my argument is correct, then GCC generates wrong code for the very
> > first example in comment #0.
> 
> I believe it does (see my #5, most probly author of some pass failed to
> check for interposition).  Note that simple recursive factorial is expanded
> to loop too which is a more impressive instance of this bug.
> 
> > To my knowledge, that
> > is the sole instance where optimization doesn't fully honor ELF
> > interposition possibility.
> 
> +1

Don't we also inline any beneficial inline functions at -O3 even if they could
be interposed (definitely not suggesting we stop doing that, that would totally
kill compiler performance)?  I'd say we shouldn't care about the semantic
interposition for self-recursion either, just make sure we don't crash on such
code.