https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108830
Bug ID: 108830
Summary: Excess warnings from -Wanalyzer-null-dereference
Product: gcc
Version: 13.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: analyzer
Assignee: dmalcolm at gcc dot gnu.org
Reporter: dmalcolm at gcc dot gnu.org
Blocks: 108562
Target Milestone: ---
Created attachment 54477
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=54477&action=edit
Reproducer
I see lots of (probable) false positives from the attached on GCC 11 through
13.
Trunk: https://godbolt.org/z/nzYreY1zx
GCC 12.2: https://godbolt.org/z/zjod5768f
GCC 11.3: https://godbolt.org/z/aeevhssG4
After the initial warning:
<source>:77:24: warning: dereference of NULL 'new_vals' [CWE-476]
[-Wanalyzer-null-dereference]
...we emit 4 further almost identical warnings.
I think they're all false positives, due to invariants we can't know about, but
presumably we should only emit the first warning: once we've determined that
we're derefing NULL 'new_vals', it doesn't make sense to repeatedly complain
each time through the loop (which is what I think is happening).
There are also a huge number of spammy "'new_vals' is NULL" messages.
Referenced Bugs:
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108562
[Bug 108562] [meta-bug] tracker bug for issues with -Wanalyzer-null-dereference
