2023-09-12 19:18:18

by Nathan Chancellor

[permalink] [raw]
Subject: [PATCH 3/7] bcachefs: Fix -Wformat in bch2_alloc_v4_invalid()

When building bcachefs for 32-bit ARM, there is a compiler warning in
bch2_alloc_v4_invalid() due to use of an incorrect format specifier:

fs/bcachefs/alloc_background.c:246:30: error: format specifies type 'unsigned long' but the argument has type 'unsigned int' [-Werror,-Wformat]
245 | prt_printf(err, "bad val size (%u > %lu)",
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
| %u
246 | alloc_v4_u64s(a.v), bkey_val_u64s(k.k));
| ~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~
fs/bcachefs/bkey.h:58:27: note: expanded from macro 'bkey_val_u64s'
58 | #define bkey_val_u64s(_k) ((_k)->u64s - BKEY_U64s)
| ^
fs/bcachefs/util.h:223:54: note: expanded from macro 'prt_printf'
223 | #define prt_printf(_out, ...) bch2_prt_printf(_out, __VA_ARGS__)
| ^~~~~~~~~~~

This expression is of type 'size_t'. On 64-bit architectures, size_t is
'unsigned long', so there is no warning when using %lu but on 32-bit
architectures, size_t is 'unsigned int'. Use '%zu', the format specifier
for 'size_t' to eliminate the warning.

Fixes: 11be8e8db283 ("bcachefs: New on disk format: Backpointers")
Signed-off-by: Nathan Chancellor <[email protected]>
---
fs/bcachefs/alloc_background.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/bcachefs/alloc_background.c b/fs/bcachefs/alloc_background.c
index 540d94c0cceb..67e73864823c 100644
--- a/fs/bcachefs/alloc_background.c
+++ b/fs/bcachefs/alloc_background.c
@@ -242,7 +242,7 @@ int bch2_alloc_v4_invalid(const struct bch_fs *c, struct bkey_s_c k,
struct bkey_s_c_alloc_v4 a = bkey_s_c_to_alloc_v4(k);

if (alloc_v4_u64s(a.v) > bkey_val_u64s(k.k)) {
- prt_printf(err, "bad val size (%u > %lu)",
+ prt_printf(err, "bad val size (%u > %zu)",
alloc_v4_u64s(a.v), bkey_val_u64s(k.k));
return -BCH_ERR_invalid_bkey;
}

--
2.42.0


2023-09-14 05:32:49

by Justin Stitt

[permalink] [raw]
Subject: Re: [PATCH 3/7] bcachefs: Fix -Wformat in bch2_alloc_v4_invalid()

On Tue, Sep 12, 2023 at 12:15:40PM -0700, Nathan Chancellor wrote:
> When building bcachefs for 32-bit ARM, there is a compiler warning in
> bch2_alloc_v4_invalid() due to use of an incorrect format specifier:
>
> fs/bcachefs/alloc_background.c:246:30: error: format specifies type 'unsigned long' but the argument has type 'unsigned int' [-Werror,-Wformat]
> 245 | prt_printf(err, "bad val size (%u > %lu)",
> | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> | %u
> 246 | alloc_v4_u64s(a.v), bkey_val_u64s(k.k));
> | ~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~
> fs/bcachefs/bkey.h:58:27: note: expanded from macro 'bkey_val_u64s'
> 58 | #define bkey_val_u64s(_k) ((_k)->u64s - BKEY_U64s)
> | ^
> fs/bcachefs/util.h:223:54: note: expanded from macro 'prt_printf'
> 223 | #define prt_printf(_out, ...) bch2_prt_printf(_out, __VA_ARGS__)
> | ^~~~~~~~~~~
>
> This expression is of type 'size_t'. On 64-bit architectures, size_t is
> 'unsigned long', so there is no warning when using %lu but on 32-bit
> architectures, size_t is 'unsigned int'. Use '%zu', the format specifier
> for 'size_t' to eliminate the warning.
>
> Fixes: 11be8e8db283 ("bcachefs: New on disk format: Backpointers")
> Signed-off-by: Nathan Chancellor <[email protected]>
Reviewed-by: Justin Stitt <[email protected]>

> ---
> fs/bcachefs/alloc_background.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/fs/bcachefs/alloc_background.c b/fs/bcachefs/alloc_background.c
> index 540d94c0cceb..67e73864823c 100644
> --- a/fs/bcachefs/alloc_background.c
> +++ b/fs/bcachefs/alloc_background.c
> @@ -242,7 +242,7 @@ int bch2_alloc_v4_invalid(const struct bch_fs *c, struct bkey_s_c k,
> struct bkey_s_c_alloc_v4 a = bkey_s_c_to_alloc_v4(k);
>
> if (alloc_v4_u64s(a.v) > bkey_val_u64s(k.k)) {
> - prt_printf(err, "bad val size (%u > %lu)",
> + prt_printf(err, "bad val size (%u > %zu)",
> alloc_v4_u64s(a.v), bkey_val_u64s(k.k));
> return -BCH_ERR_invalid_bkey;
> }
>
> --
> 2.42.0
>