Re: [PATCH v3 22/22] fsdep/9p: fix -Werror=maybe-uninitialized false-positive

[Christian Schoenebeck via <qemu-devel@nongnu.org>]

On Monday, September 30, 2024 10:14:57 AM CEST Marc-André Lureau wrote:
> From: Marc-André Lureau <marcandre.lureau@redhat.com>
> 
> ../fsdev/9p-iov-marshal.c:93:23: error: ‘val’ may be used uninitialized [-Werror=maybe-uninitialized]
> and similar
> 
> Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
> ---
>  fsdev/9p-iov-marshal.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/fsdev/9p-iov-marshal.c b/fsdev/9p-iov-marshal.c
> index a1c9beddd2..75fb87a490 100644
> --- a/fsdev/9p-iov-marshal.c
> +++ b/fsdev/9p-iov-marshal.c
> @@ -84,7 +84,7 @@ ssize_t v9fs_iov_vunmarshal(struct iovec *out_sg, int out_num, size_t offset,
>              break;
>          }
>          case 'w': {
> -            uint16_t val, *valp;
> +            uint16_t val = 0, *valp;
>              valp = va_arg(ap, uint16_t *);
>              copied = v9fs_unpack(&val, out_sg, out_num, offset, sizeof(val));

Another option would be inserting here:

	if (copied <= 0) break;

Same below. But I leave it up to you:

Reviewed-by: Christian Schoenebeck <qemu_oss@crudebyte.com>

/Christian

>              if (bswap) {
> @@ -95,7 +95,7 @@ ssize_t v9fs_iov_vunmarshal(struct iovec *out_sg, int out_num, size_t offset,
>              break;
>          }
>          case 'd': {
> -            uint32_t val, *valp;
> +            uint32_t val = 0, *valp;
>              valp = va_arg(ap, uint32_t *);
>              copied = v9fs_unpack(&val, out_sg, out_num, offset, sizeof(val));
>              if (bswap) {
> @@ -106,7 +106,7 @@ ssize_t v9fs_iov_vunmarshal(struct iovec *out_sg, int out_num, size_t offset,
>              break;
>          }
>          case 'q': {
> -            uint64_t val, *valp;
> +            uint64_t val = 0, *valp;
>              valp = va_arg(ap, uint64_t *);
>              copied = v9fs_unpack(&val, out_sg, out_num, offset, sizeof(val));
>              if (bswap) {
>