On Tue, Sep 12, 2023 at 12:15:39PM -0700, Nathan Chancellor wrote:
> When building bcachefs for 32-bit ARM, there is a compiler warning in
> bch2_btree_key_cache_to_text() due to use of an incorrect format
> specifier:
>
> fs/bcachefs/btree_key_cache.c:1060:36: error: format specifies type
> 'size_t' (aka 'unsigned int') but the argument has type 'long'
> [-Werror,-Wformat]
> 1060 | prt_printf(out, "nr_freed:\t%zu",
> atomic_long_read(&c->nr_freed));
> | ~~~
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> | %ld
> fs/bcachefs/util.h:223:54: note: expanded from macro 'prt_printf'
> 223 | #define prt_printf(_out, ...) bch2_prt_printf(_out,
> __VA_ARGS__)
> |
> ^~~~~~~~~~~
> 1 error generated.
>
> On 64-bit architectures, size_t is 'unsigned long', so there is no
> warning when using %zu but on 32-bit architectures, size_t is
> 'unsigned int'. Use '%lu' to match the other format specifiers used in
> this function for printing values returned from atomic_long_read().
>
> Fixes: 6d799930ce0f ("bcachefs: btree key cache pcpu freedlist")
> Signed-off-by: Nathan Chancellor <[email protected]>
Reviewed-by: Justin Stitt <[email protected]>
> ---
> fs/bcachefs/btree_key_cache.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/fs/bcachefs/btree_key_cache.c b/fs/bcachefs/btree_key_cache.c
> index 505e7c365ab7..a74ee6d8a7cf 100644
> --- a/fs/bcachefs/btree_key_cache.c
> +++ b/fs/bcachefs/btree_key_cache.c
> @@ -1053,7 +1053,7 @@ int bch2_fs_btree_key_cache_init(struct btree_key_cache
> *bc)
>
> void bch2_btree_key_cache_to_text(struct printbuf *out, struct
> btree_key_cache *c)
> {
> - prt_printf(out, "nr_freed:\t%zu", atomic_long_read(&c->nr_freed));
> + prt_printf(out, "nr_freed:\t%lu", atomic_long_read(&c->nr_freed));
> prt_newline(out);
> prt_printf(out, "nr_keys:\t%lu", atomic_long_read(&c->nr_keys));
> prt_newline(out);
>
> --
> 2.42.0
>
