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From: "jan.zizka at nokia dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/110437] SIGILL when return missing in a C++ function with a
 condition
Date: Wed, 28 Jun 2023 08:02:30 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D110437

--- Comment #12 from Jan =C5=BDi=C5=BEka <jan.zizka at nokia dot com> ---
(In reply to Xi Ruoyao from comment #11)
> is perfectly legal if the caller doesn't pass anything other than 1 or 42=
 to
> f.  So we cannot just reject it at the compile time, we can only issue a
> warning.

True that, still this doesn't make it sound software implementation :-)

Another example pointed out by one colleague of mine:

int f(int a)
{
  if (a =3D=3D 1)
    exit(0);
  else
    return 0xbeef;
}

> And generally there is no way to determine if an "unsupported" value is
> passed to f at compile time because doing so will need to solve the halti=
ng
> problem.

That is true :-) but from software implementation if you reuse such a funct=
ion
or it is a library I'd personally disallow this as this is bad coding. But =
this
will be opinionated so better not to dive to such a rabbit hole.

Thanks for comments.=