[PATCH] btrfs: work around false-positive -Wsometimes-uninitialized warning

From: Arnd Bergmann
Date: Fri Mar 22 2019 - 10:08:45 EST


clang fails to see that the last 'else if() in btrfs_uuid_tree_add()
is always true, so 'eb' is always initialized correctly:

fs/btrfs/uuid-tree.c:129:13: error: variable 'eb' is used uninitialized whenever 'if' condition is false [-Werror,-Wsometimes-uninitialized]
} else if (ret < 0) {
^~~~~~~
fs/btrfs/uuid-tree.c:139:22: note: uninitialized use occurs here
write_extent_buffer(eb, &subid_le, offset, sizeof(subid_le));
^~
fs/btrfs/uuid-tree.c:129:9: note: remove the 'if' if its condition is always true
} else if (ret < 0) {
^~~~~~~~~~~~~
fs/btrfs/uuid-tree.c:90:26: note: initialize the variable 'eb' to silence this warning
struct extent_buffer *eb;
^
= NULL

Change it into a plain 'else' to shut up that warning.

Link: https://bugs.llvm.org/show_bug.cgi?id=41197
Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
---
fs/btrfs/uuid-tree.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/btrfs/uuid-tree.c b/fs/btrfs/uuid-tree.c
index 3b2ae342e649..c1cc9a5c0024 100644
--- a/fs/btrfs/uuid-tree.c
+++ b/fs/btrfs/uuid-tree.c
@@ -126,7 +126,7 @@ int btrfs_uuid_tree_add(struct btrfs_trans_handle *trans, u8 *uuid, u8 type,
slot = path->slots[0];
offset = btrfs_item_ptr_offset(eb, slot);
offset += btrfs_item_size_nr(eb, slot) - sizeof(subid_le);
- } else if (ret < 0) {
+ } else {
btrfs_warn(fs_info,
"insert uuid item failed %d (0x%016llx, 0x%016llx) type %u!",
ret, (unsigned long long)key.objectid,
--
2.20.0