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dkim=pass header.d=foxmail.com header.s=s201512 header.b=Ehmt7HFh; dmarc=pass (policy=none) header.from=foxmail.com; spf=pass (imf02.hostedemail.com: domain of rtoax@foxmail.com designates 203.205.221.209 as permitted sender) smtp.mailfrom=rtoax@foxmail.com X-Rspam-User: X-Rspamd-Server: rspam01 X-Stat-Signature: 4f1h5uojz36utraqaq4hiwgk3ffmcegt X-HE-Tag: 1668056453-398082 X-Bogosity: Ham, tests=bogofilter, spamicity=0.054968, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: Rong Tao We need to set an initial value for offset to eliminate compilation warning. And if the tree is empty, return NULL early. How to reproduce warning: $ make -C tools/testing/radix-tree radix-tree.c: In function ‘radix_tree_tag_clear’: radix-tree.c:1046:17: warning: ‘offset’ may be used uninitialized in this function [-Wmaybe-uninitialized] 1046 | node_tag_clear(root, parent, tag, offset); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Signed-off-by: Rong Tao --- lib/radix-tree.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/lib/radix-tree.c b/lib/radix-tree.c index 3c78e1e8b2ad..eee453b856b6 100644 --- a/lib/radix-tree.c +++ b/lib/radix-tree.c @@ -1029,10 +1029,10 @@ void *radix_tree_tag_clear(struct radix_tree_root *root, { struct radix_tree_node *node, *parent; unsigned long maxindex; - int offset; + int offset = 0; radix_tree_load_root(root, &node, &maxindex); - if (index > maxindex) + if (index > maxindex || !node) return NULL; parent = NULL;