Re: [PATCH] btrfs: send: Silence build warning about kvcalloc()

From: David Sterba
Date: Mon Jan 08 2024 - 12:50:49 EST


On Mon, Jan 08, 2024 at 12:13:51PM +0800, Tiezhu Yang wrote:
> There exist the following warning when building kernel v6.7:
>
> CC fs/btrfs/send.o
> fs/btrfs/send.c: In function ‘btrfs_ioctl_send’:
> fs/btrfs/send.c:8208:44: warning: ‘kvcalloc’ sizes specified with ‘sizeof’ in the earlier argument and not in the later argument [-Wcalloc-transposed-args]
> 8208 | sctx->clone_roots = kvcalloc(sizeof(*sctx->clone_roots),
> | ^
> fs/btrfs/send.c:8208:44: note: earlier argument should specify number of elements, later size of each element
>
> tested with the latest upstream toolchains (20240105):
>
> [fedora@linux 6.7.test]$ gcc --version
> gcc (GCC) 14.0.0 20240105 (experimental)
> [fedora@linux 6.7.test]$ as --version
> GNU assembler (GNU Binutils) 2.41.50.20240105
> [fedora@linux 6.7.test]$ ld --version
> GNU ld (GNU Binutils) 2.41.50.20240105
>
> just switch the first and second arguments of kvcalloc() to silence
> the build warning, compile tested only.
>
> Fixes: bae12df966f0 ("btrfs: use kvcalloc for allocation in btrfs_ioctl_send()")
> Signed-off-by: Tiezhu Yang <yangtiezhu@xxxxxxxxxxx>

Thanks, a fix has been already sent
https://lore.kernel.org/linux-btrfs/20231221084748.10094-1-dmantipov@xxxxxxxxx/