On 16.11.18 г. 9:54 ч., Qu Wenruo wrote:
> The only location is the following code:
>
> int level = path->lowest_level + 1;
> BUG_ON(path->lowest_level + 1 >= BTRFS_MAX_LEVEL);
> while(level < BTRFS_MAX_LEVEL) {
> slot = path->slots[level] + 1;
> ...
> }
> path->slots[level] = slot;
>
> Again, it's the stupid compiler needs some hint for the fact that
> we will always enter the while loop for at least once, thus @slot should
> always be initialized.
>
> Fix it by assign level after the BUG_ON(), so the stupid compiler knows
> we will always go into the while loop.
>
> Signed-off-by: Qu Wenruo <w...@suse.com>
I don't get this warning on gcc 7.3. Also from your changelog it's not
really clear what the compiler is confused about.
Codewise lgtm:
Reviewed-by: Nikolay Borisov <nbori...@suse.com>
> ---
> ctree.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/ctree.c b/ctree.c
> index 46e2ccedc0bf..9c9cb0dfdbf2 100644
> --- a/ctree.c
> +++ b/ctree.c
> @@ -2961,11 +2961,12 @@ int btrfs_next_sibling_tree_block(struct
> btrfs_fs_info *fs_info,
> struct btrfs_path *path)
> {
> int slot;
> - int level = path->lowest_level + 1;
> + int level;
> struct extent_buffer *c;
> struct extent_buffer *next = NULL;
>
> BUG_ON(path->lowest_level + 1 >= BTRFS_MAX_LEVEL);
> + level = path->lowest_level + 1;
> while(level < BTRFS_MAX_LEVEL) {
> if (!path->nodes[level])
> return 1;
>
