Commit 67893f12 authored Jan 26, 2016 by Arnd Bergmann Committed by Bob Peterson Mar 15, 2016

gfs2: avoid uninitialized variable warning



We get a bogus warning about a potential uninitialized variable
use in gfs2, because the compiler does not figure out that we
never use the leaf number if get_leaf_nr() returns an error:

fs/gfs2/dir.c: In function 'get_first_leaf':
fs/gfs2/dir.c:802:9: warning: 'leaf_no' may be used uninitialized in this function [-Wmaybe-uninitialized]
fs/gfs2/dir.c: In function 'dir_split_leaf':
fs/gfs2/dir.c:1021:8: warning: 'leaf_no' may be used uninitialized in this function [-Wmaybe-uninitialized]

Changing the 'if (!error)' to 'if (!IS_ERR_VALUE(error))' is
sufficient to let gcc understand that this is exactly the same
condition as in IS_ERR() so it can optimize the code path enough
to understand it.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>

parent 7508abc4

fs/gfs2/dir.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -798,7 +798,7 @@ static int get_first_leaf(struct gfs2_inode *dip, u32 index,
		int error;

		error = get_leaf_nr(dip, index, &leaf_no);
		if (!error)
		if (!IS_ERR_VALUE(error))
		error = get_leaf(dip, leaf_no, bh_out);

		return error;
		@@ -1014,7 +1014,7 @@ static int dir_split_leaf(struct inode inode, const struct qstr name)

		index = name->hash >> (32 - dip->i_depth);
		error = get_leaf_nr(dip, index, &leaf_no);
		if (error)
		if (IS_ERR_VALUE(error))
		return error;

		/* Get the old leaf block */

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