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* [Bug analyzer/110520] New: -Wanalyzer-null-dereference false nagetive with `*ptr = 10086`
@ 2023-07-02 12:30 dale.mengli.ming at proton dot me
2023-09-06 21:37 ` [Bug analyzer/110520] " dmalcolm at gcc dot gnu.org
` (3 more replies)
0 siblings, 4 replies; 5+ messages in thread
From: dale.mengli.ming at proton dot me @ 2023-07-02 12:30 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110520
Bug ID: 110520
Summary: -Wanalyzer-null-dereference false nagetive with `*ptr
= 10086`
Product: gcc
Version: 14.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: analyzer
Assignee: dmalcolm at gcc dot gnu.org
Reporter: dale.mengli.ming at proton dot me
Target Milestone: ---
Hi,in this case (https://godbolt.org/z/4Md3o94Gx), the `ptr` is a null pointer,
but the analyzer doesn't report an NPD with it. When `__builtin_strlen(buf) ==
0` (https://godbolt.org/z/fnbMY9W5z), the analyzer reports that.
^ permalink raw reply [flat|nested] 5+ messages in thread* [Bug analyzer/110520] -Wanalyzer-null-dereference false nagetive with `*ptr = 10086` 2023-07-02 12:30 [Bug analyzer/110520] New: -Wanalyzer-null-dereference false nagetive with `*ptr = 10086` dale.mengli.ming at proton dot me @ 2023-09-06 21:37 ` dmalcolm at gcc dot gnu.org 2023-10-25 8:18 ` dale.mengli.ming at proton dot me ` (2 subsequent siblings) 3 siblings, 0 replies; 5+ messages in thread From: dmalcolm at gcc dot gnu.org @ 2023-09-06 21:37 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110520 David Malcolm <dmalcolm at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Ever confirmed|0 |1 Status|UNCONFIRMED |ASSIGNED Last reconfirmed| |2023-09-06 --- Comment #1 from David Malcolm <dmalcolm at gcc dot gnu.org> --- Thanks for filing this bug. With trunk (for gcc 14) I correctly get a NPD warning (true positive): https://godbolt.org/z/a5h38cz7d With gcc 13.2, I don't (false negative): https://godbolt.org/z/PKnToYK8v I've been rewriting C string handling for gcc 14, so it's likely this now working is a side-effect of that. Keeping open to track adding a regression test for this. ^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug analyzer/110520] -Wanalyzer-null-dereference false nagetive with `*ptr = 10086` 2023-07-02 12:30 [Bug analyzer/110520] New: -Wanalyzer-null-dereference false nagetive with `*ptr = 10086` dale.mengli.ming at proton dot me 2023-09-06 21:37 ` [Bug analyzer/110520] " dmalcolm at gcc dot gnu.org @ 2023-10-25 8:18 ` dale.mengli.ming at proton dot me 2024-02-19 23:10 ` [Bug analyzer/110520] -Wanalyzer-null-dereference false negative " cvs-commit at gcc dot gnu.org 2024-02-19 23:15 ` dmalcolm at gcc dot gnu.org 3 siblings, 0 replies; 5+ messages in thread From: dale.mengli.ming at proton dot me @ 2023-10-25 8:18 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110520 --- Comment #2 from mengli ming <dale.mengli.ming at proton dot me> --- (In reply to David Malcolm from comment #1) > Thanks for filing this bug. > > With trunk (for gcc 14) I correctly get a NPD warning (true positive): > https://godbolt.org/z/a5h38cz7d > > With gcc 13.2, I don't (false negative): > https://godbolt.org/z/PKnToYK8v > > I've been rewriting C string handling for gcc 14, so it's likely this now > working is a side-effect of that. > > Keeping open to track adding a regression test for this. Thank you for your explanation. (^_^) ^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug analyzer/110520] -Wanalyzer-null-dereference false negative with `*ptr = 10086` 2023-07-02 12:30 [Bug analyzer/110520] New: -Wanalyzer-null-dereference false nagetive with `*ptr = 10086` dale.mengli.ming at proton dot me 2023-09-06 21:37 ` [Bug analyzer/110520] " dmalcolm at gcc dot gnu.org 2023-10-25 8:18 ` dale.mengli.ming at proton dot me @ 2024-02-19 23:10 ` cvs-commit at gcc dot gnu.org 2024-02-19 23:15 ` dmalcolm at gcc dot gnu.org 3 siblings, 0 replies; 5+ messages in thread From: cvs-commit at gcc dot gnu.org @ 2024-02-19 23:10 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110520 --- Comment #3 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by David Malcolm <dmalcolm@gcc.gnu.org>: https://gcc.gnu.org/g:eb37ea529745c38dcf86c3cdbedb66df69ea9e35 commit r14-9075-geb37ea529745c38dcf86c3cdbedb66df69ea9e35 Author: David Malcolm <dmalcolm@redhat.com> Date: Mon Feb 19 18:07:59 2024 -0500 analyzer, testsuite: add regression test [PR110520] gcc/testsuite/ChangeLog: PR analyzer/110520 * c-c++-common/analyzer/null-deref-pr110520.c: New test. Signed-off-by: David Malcolm <dmalcolm@redhat.com> ^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug analyzer/110520] -Wanalyzer-null-dereference false negative with `*ptr = 10086` 2023-07-02 12:30 [Bug analyzer/110520] New: -Wanalyzer-null-dereference false nagetive with `*ptr = 10086` dale.mengli.ming at proton dot me ` (2 preceding siblings ...) 2024-02-19 23:10 ` [Bug analyzer/110520] -Wanalyzer-null-dereference false negative " cvs-commit at gcc dot gnu.org @ 2024-02-19 23:15 ` dmalcolm at gcc dot gnu.org 3 siblings, 0 replies; 5+ messages in thread From: dmalcolm at gcc dot gnu.org @ 2024-02-19 23:15 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110520 David Malcolm <dmalcolm at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Resolution|--- |FIXED Status|ASSIGNED |RESOLVED --- Comment #4 from David Malcolm <dmalcolm at gcc dot gnu.org> --- (In reply to David Malcolm from comment #1) > Keeping open to track adding a regression test for this. Regression test added; closing. ^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2024-02-19 23:15 UTC | newest] Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2023-07-02 12:30 [Bug analyzer/110520] New: -Wanalyzer-null-dereference false nagetive with `*ptr = 10086` dale.mengli.ming at proton dot me 2023-09-06 21:37 ` [Bug analyzer/110520] " dmalcolm at gcc dot gnu.org 2023-10-25 8:18 ` dale.mengli.ming at proton dot me 2024-02-19 23:10 ` [Bug analyzer/110520] -Wanalyzer-null-dereference false negative " cvs-commit at gcc dot gnu.org 2024-02-19 23:15 ` dmalcolm at gcc dot gnu.org
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