Re: [PATCH] MIPS: Make BUG() __noreturn.

From: Geert Uytterhoeven
Date: Fri Nov 21 2008 - 05:28:03 EST


On Fri, 21 Nov 2008, Alan Cox wrote:
> On Thu, 20 Nov 2008 17:26:36 -0800
> David Daney <ddaney@xxxxxxxxxxxxxxxxxx> wrote:
>
> > MIPS: Make BUG() __noreturn.
> >
> > Often we do things like put BUG() in the default clause of a case
> > statement. Since it was not declared __noreturn, this could sometimes
> > lead to bogus compiler warnings that variables were used
> > uninitialized.
> >
> > There is a small problem in that we have to put a magic while(1); loop to
> > fool GCC into really thinking it is noreturn.
>
> That sounds like your __noreturn macro is wrong.
>
> Try using __attribute__ ((__noreturn__))
>
> if that works then fix up the __noreturn definitions for the MIPS and gcc
> you have.

Nope, gcc is too smart:

$ cat a.c

int f(void) __attribute__((__noreturn__));

int f(void)
{
}

$ gcc -c -Wall a.c
a.c: In function f:
a.c:6: warning: `noreturn' function does return
$

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
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