Re: [PATCH -mm] sys_semctl gcc 4.1 warning fix

[Alan Cox <alan@lxorguk.ukuu.org.uk>]

On Maw, 2006-05-09 at 19:56 -0700, Daniel Walker wrote:
> Fixes the following warnings,
> 
> ipc/sem.c: In function 'sys_semctl':
> ipc/sem.c:810: warning: 'setbuf.uid' may be used uninitialized in this function
> ipc/sem.c:810: warning: 'setbuf.gid' may be used uninitialized in this function
> ipc/sem.c:810: warning: 'setbuf.mode' may be used uninitialized in this function
> 
> Signed-Off-By: Daniel Walker <dwalker@mvista.com>
> 
> Index: linux-2.6.16/ipc/sem.c
> ===================================================================
> --- linux-2.6.16.orig/ipc/sem.c
> +++ linux-2.6.16/ipc/sem.c
> @@ -807,7 +807,7 @@ static int semctl_down(int semid, int se
>  {
>  	struct sem_array *sma;
>  	int err;
> -	struct sem_setbuf setbuf;
> +	struct sem_setbuf setbuf = {0, 0, 0};


This causes very poor code as its initializing an object on the stack.
It also appears from inspection to be entirely un-neccessary. Instead
the compiler needs some help.

Hiding warnings like this can be a hazard as it will hide real warnings
later on.