Re: [PATCH] ext4: Fix unused iterator variable warnings

[Jan Kara]

On Thu 20-04-23 09:51:24, Nathan Chancellor wrote:
> When CONFIG_QUOTA is disabled, there are warnings around unused iterator
> variables:
> 
>   fs/ext4/super.c: In function 'ext4_put_super':
>   fs/ext4/super.c:1262:13: error: unused variable 'i' [-Werror=unused-variable]
>    1262 |         int i, err;
>         |             ^
>   fs/ext4/super.c: In function '__ext4_fill_super':
>   fs/ext4/super.c:5200:22: error: unused variable 'i' [-Werror=unused-variable]
>    5200 |         unsigned int i;
>         |                      ^
>   cc1: all warnings being treated as errors
> 
> The kernel has updated to gnu11, allowing the variables to be declared
> within the for loop. Do so to clear up the warnings.
> 
> Fixes: dcbf87589d90 ("ext4: factor out ext4_flex_groups_free()")
> Signed-off-by: Nathan Chancellor <nathan@xxxxxxxxxx>

Looks good. Feel free to add:

Reviewed-by: Jan Kara <jack@xxxxxxx>

								Honza

> ---
>  fs/ext4/super.c | 7 +++----
>  1 file changed, 3 insertions(+), 4 deletions(-)
> 
> diff --git a/fs/ext4/super.c b/fs/ext4/super.c
> index 403cc0e6cd65..f16492b8c98d 100644
> --- a/fs/ext4/super.c
> +++ b/fs/ext4/super.c
> @@ -1259,7 +1259,7 @@ static void ext4_put_super(struct super_block *sb)
>  	struct ext4_sb_info *sbi = EXT4_SB(sb);
>  	struct ext4_super_block *es = sbi->s_es;
>  	int aborted = 0;
> -	int i, err;
> +	int err;
>  
>  	/*
>  	 * Unregister sysfs before destroying jbd2 journal.
> @@ -1311,7 +1311,7 @@ static void ext4_put_super(struct super_block *sb)
>  	ext4_flex_groups_free(sbi);
>  	ext4_percpu_param_destroy(sbi);
>  #ifdef CONFIG_QUOTA
> -	for (i = 0; i < EXT4_MAXQUOTAS; i++)
> +	for (int i = 0; i < EXT4_MAXQUOTAS; i++)
>  		kfree(get_qf_name(sb, sbi, i));
>  #endif
>  
> @@ -5197,7 +5197,6 @@ static int __ext4_fill_super(struct fs_context *fc, struct super_block *sb)
>  	ext4_fsblk_t logical_sb_block;
>  	struct inode *root;
>  	int ret = -ENOMEM;
> -	unsigned int i;
>  	int needs_recovery;
>  	int err = 0;
>  	ext4_group_t first_not_zeroed;
> @@ -5628,7 +5627,7 @@ static int __ext4_fill_super(struct fs_context *fc, struct super_block *sb)
>  #endif
>  
>  #ifdef CONFIG_QUOTA
> -	for (i = 0; i < EXT4_MAXQUOTAS; i++)
> +	for (unsigned int i = 0; i < EXT4_MAXQUOTAS; i++)
>  		kfree(get_qf_name(sb, sbi, i));
>  #endif
>  	fscrypt_free_dummy_policy(&sbi->s_dummy_enc_policy);
> 
> ---
> base-commit: 519fe1bae7e20fc4e7f179d50b6102b49980e85d
> change-id: 20230420-ext4-unused-variables-super-c-cabda558d931
> 
> Best regards,
> -- 
> Nathan Chancellor <nathan@xxxxxxxxxx>
> 
-- 
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR