From mboxrd@z Thu Jan  1 00:00:00 1970
From: Johannes Sixt <j.sixt@viscovery.net>
Subject: Re: [PATCH 2/2] remove NORETURN from function pointers
Date: Mon, 14 Sep 2009 15:09:27 +0200
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Cc: Jeff King <peff@peff.net>, git@vger.kernel.org,
	Erik Faye-Lund <kusmabite@gmail.com>
To: Erik Faye-Lund <kusmabite@googlemail.com>
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Erik Faye-Lund schrieb:
> Compiling the following code gives a warning about unreachable code,
> so it's clear that msvc doesn't simply ignore the directive. I'm not
> saying that anyone suggested otherwise, I just wanted to know for
> sure.
> 
> #include <stdio.h>
> #include <stdlib.h>
> void (*exit_fun)(int) = exit;
> void __declspec(noreturn) die(void);
> void die(void) { exit_fun(1); }
> int main(void) { printf("hello!\n"); die(); printf("world!\n"); }

In order to countermand any clever optimizations you should make it

-void (*exit_fun)(int) = exit;
+extern void (*exit_fun)(int);

(of course, this fails to link). But if this results in only *one* warning
(that the printf() call is unreachable), then I wouldn't bother with this
problem anymore, because you really should also have been warned that a
__declspec(noreturn) function actually does return.

-- Hannes