[PATCH] NFSD: Remove redundant assignment to variable host_err

[PATCH] NFSD: Remove redundant assignment to variable host_err

[Colin Ian King]

Variable host_err is assigned a value that is never read, it is being
re-assigned a value in every different execution path in the following
switch statement. The assignment is redundant and can be removed.

Cleans up clang-scan warning:
warning: Value stored to 'host_err' is never read [deadcode.DeadStores]

Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
---
 fs/nfsd/vfs.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index f650afedd67f..5093ae788f53 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -1304,7 +1304,6 @@ nfsd_create_locked(struct svc_rqst *rqstp, struct svc_fh *fhp,
 		iap->ia_mode &= ~current_umask();
 
 	err = 0;
-	host_err = 0;
 	switch (type) {
 	case S_IFREG:
 		host_err = vfs_create(&init_user_ns, dirp, dchild, iap->ia_mode, true);
-- 
2.37.3

Re: [PATCH] NFSD: Remove redundant assignment to variable host_err

[Jeff Layton]

On Mon, 2022-10-10 at 21:24 +0100, Colin Ian King wrote:
> Variable host_err is assigned a value that is never read, it is being
> re-assigned a value in every different execution path in the following
> switch statement. The assignment is redundant and can be removed.
> 
> Cleans up clang-scan warning:
> warning: Value stored to 'host_err' is never read [deadcode.DeadStores]
> 

The warning is a bit odd since it _is_ read at the bottom of the
function:

        err = nfserrno(host_err);                                     

...but, all of the switch cases end up setting host_err, so the
initialization isn't needed.

> Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
> ---
>  fs/nfsd/vfs.c | 1 -
>  1 file changed, 1 deletion(-)
> 
> diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
> index f650afedd67f..5093ae788f53 100644
> --- a/fs/nfsd/vfs.c
> +++ b/fs/nfsd/vfs.c
> @@ -1304,7 +1304,6 @@ nfsd_create_locked(struct svc_rqst *rqstp, struct svc_fh *fhp,
>  		iap->ia_mode &= ~current_umask();
>  
>  	err = 0;
> -	host_err = 0;
>  	switch (type) {
>  	case S_IFREG:
>  		host_err = vfs_create(&init_user_ns, dirp, dchild, iap->ia_mode, true);

Reviewed-by: Jeff Layton <jlayton@kernel.org>

Re: [PATCH] NFSD: Remove redundant assignment to variable host_err

[Chuck Lever III]

> On Oct 10, 2022, at 4:24 PM, Colin Ian King <colin.i.king@gmail.com> wrote:
> 
> Variable host_err is assigned a value that is never read, it is being
> re-assigned a value in every different execution path in the following
> switch statement. The assignment is redundant and can be removed.
> 
> Cleans up clang-scan warning:
> warning: Value stored to 'host_err' is never read [deadcode.DeadStores]
> 
> Signed-off-by: Colin Ian King <colin.i.king@gmail.com>

Applying this for nfsd's for-next (not yet public). Thanks!



> ---
> fs/nfsd/vfs.c | 1 -
> 1 file changed, 1 deletion(-)
> 
> diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
> index f650afedd67f..5093ae788f53 100644
> --- a/fs/nfsd/vfs.c
> +++ b/fs/nfsd/vfs.c
> @@ -1304,7 +1304,6 @@ nfsd_create_locked(struct svc_rqst *rqstp, struct svc_fh *fhp,
> 		iap->ia_mode &= ~current_umask();
> 
> 	err = 0;
> -	host_err = 0;
> 	switch (type) {
> 	case S_IFREG:
> 		host_err = vfs_create(&init_user_ns, dirp, dchild, iap->ia_mode, true);
> -- 
> 2.37.3
> 

--
Chuck Lever