From: Arnd Bergmann Date: Wed, 2 Nov 2016 13:52:15 +0000 (+0100) Subject: f2fs: hide a maybe-uninitialized warning X-Git-Tag: v5.15~12288^2~43 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=230436b3ef3fd7d4a1da19edf5e87bb2d74e0fc2;p=platform%2Fkernel%2Flinux-starfive.git f2fs: hide a maybe-uninitialized warning gcc is unsure about the use of last_ofs_in_node, which might happen without a prior initialization: fs/f2fs//git/arm-soc/fs/f2fs/data.c: In function ‘f2fs_map_blocks’: fs/f2fs/data.c:799:54: warning: ‘last_ofs_in_node’ may be used uninitialized in this function [-Wmaybe-uninitialized] if (prealloc && dn.ofs_in_node != last_ofs_in_node + 1) { As pointed out by Chao Yu, the code is actually correct as 'prealloc' is only set if the last_ofs_in_node has been set, the two always get updated together. This initializes last_ofs_in_node to dn.ofs_in_node for each new dnode at the start of the 'next_block' loop, which at that point is a correct initialization as well. I assume that compilers that correctly track the contents of the variables and do not warn about the condition also figure out that they can eliminate the extra assignment here. Fixes: 46008c6d4232 ("f2fs: support in batch multi blocks preallocation") Signed-off-by: Arnd Bergmann Signed-off-by: Jaegeuk Kim --- diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c index 68edb47..cf5ec39 100644 --- a/fs/f2fs/data.c +++ b/fs/f2fs/data.c @@ -713,7 +713,7 @@ next_dnode: } prealloc = 0; - ofs_in_node = dn.ofs_in_node; + last_ofs_in_node = ofs_in_node = dn.ofs_in_node; end_offset = ADDRS_PER_PAGE(dn.node_page, inode); next_block: