Re: [PATCH] jfs: fix bogus variable self-initialization

From: Dave Kleikamp
Date: Fri Mar 22 2019 - 10:41:45 EST


On 3/22/19 9:19 AM, Arnd Bergmann wrote:
> A statement was originally added in 2006 to shut up a gcc warning,
> now but now clang warns about it:
>
> fs/jfs/jfs_txnmgr.c:1932:15: error: variable 'pxd' is uninitialized when used within its own initialization
> [-Werror,-Wuninitialized]
> pxd_t pxd = pxd; /* truncated extent of xad */
> ~~~ ^~~
>
> Modern versions of gcc are fine without the silly assignment, so just
> drop it. Tested with gcc-4.6 (released 2011), 4.7, 4.8, and 4.9.

Thanks Arnd. Will push it upstream.

Shaggy

>
> Fixes: c9e3ad6021e5 ("JFS: Get rid of "may be used uninitialized" warnings")
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
Signed-off-by: Dave Kleikamp <dave.kleikamp@xxxxxxxxxx>

> ---
> fs/jfs/jfs_txnmgr.c | 3 +--
> 1 file changed, 1 insertion(+), 2 deletions(-)
>
> diff --git a/fs/jfs/jfs_txnmgr.c b/fs/jfs/jfs_txnmgr.c
> index a5663cb621d8..78789c5ed36b 100644
> --- a/fs/jfs/jfs_txnmgr.c
> +++ b/fs/jfs/jfs_txnmgr.c
> @@ -1928,8 +1928,7 @@ static void xtLog(struct jfs_log * log, struct tblock * tblk, struct lrd * lrd,
> * header ?
> */
> if (tlck->type & tlckTRUNCATE) {
> - /* This odd declaration suppresses a bogus gcc warning */
> - pxd_t pxd = pxd; /* truncated extent of xad */
> + pxd_t pxd; /* truncated extent of xad */
> int twm;
>
> /*
>