linux-next: build warnings after merge of the btrfs tree

From: Stephen Rothwell
Date: Mon Sep 11 2023 - 23:03:29 EST


Hi all,

After merging the btrfs tree, today's linux-next build (powerpc
ppc64_defconfig) produced these warnings:

In file included from include/linux/swab.h:5,
from include/uapi/linux/byteorder/big_endian.h:14,
from include/linux/byteorder/big_endian.h:5,
from arch/powerpc/include/uapi/asm/byteorder.h:14,
from include/asm-generic/bitops/le.h:6,
from arch/powerpc/include/asm/bitops.h:336,
from include/linux/bitops.h:68,
from fs/btrfs/extent_io.c:3:
In function 'btrfs_disk_key_to_cpu',
inlined from 'btrfs_item_key_to_cpu' at fs/btrfs/accessors.h:648:2,
inlined from 'fiemap_find_last_extent_offset' at fs/btrfs/extent_io.c:2804:2,
inlined from 'extent_fiemap' at fs/btrfs/extent_io.c:2879:8:
include/uapi/linux/swab.h:128:28: warning: 'disk_key.objectid' may be used uninitialized [-Wmaybe-uninitialized]
128 | #define __swab64(x) (__u64)__builtin_bswap64((__u64)(x))
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/uapi/linux/byteorder/big_endian.h:33:26: note: in expansion of macro '__swab64'
33 | #define __le64_to_cpu(x) __swab64((__force __u64)(__le64)(x))
| ^~~~~~~~
include/linux/byteorder/generic.h:87:21: note: in expansion of macro '__le64_to_cpu'
87 | #define le64_to_cpu __le64_to_cpu
| ^~~~~~~~~~~~~
fs/btrfs/accessors.h:622:25: note: in expansion of macro 'le64_to_cpu'
622 | cpu->objectid = le64_to_cpu(disk->objectid);
| ^~~~~~~~~~~
In file included from fs/btrfs/extent_io.c:34:
fs/btrfs/accessors.h: In function 'extent_fiemap':
fs/btrfs/accessors.h:645:31: note: 'disk_key.objectid' was declared here
645 | struct btrfs_disk_key disk_key;
| ^~~~~~~~
In function 'fiemap_find_last_extent_offset',
inlined from 'extent_fiemap' at fs/btrfs/extent_io.c:2879:8:
fs/btrfs/extent_io.c:2805:33: warning: 'disk_key.type' may be used uninitialized [-Wmaybe-uninitialized]
2805 | if (key.objectid != ino || key.type != BTRFS_EXTENT_DATA_KEY) {
fs/btrfs/accessors.h: In function 'extent_fiemap':
fs/btrfs/accessors.h:645:31: note: 'disk_key.type' was declared here
645 | struct btrfs_disk_key disk_key;
| ^~~~~~~~

I don't really have any idea what caused this (it *may* have been my
change from gcc v12 to v13?).

--
Cheers,
Stephen Rothwell

Attachment: pgprqKgIn7fSx.pgp
Description: OpenPGP digital signature