https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110543
Bug ID: 110543
Summary: RFE: Add optional trim of the analyzer diagnostics
through system headers.
Product: gcc
Version: unknown
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: analyzer
Assignee: dmalcolm at gcc dot gnu.org
Reporter: vultkayn at gcc dot gnu.org
Target Milestone: ---
See https://godbolt.org/z/sb9dM9Gqa for a reproducer on trunk.
Given an issue on std::shared_ptr<>, the analyzer emits a path that I'd like to
optionally shorten, by trimming it.
Looking at the reproducer, I believe it would be desirable the analyzer emits
similar diagnostics for smart pointers as it is for raw pointers, i.e. the
diagnostic should not dive into the standard library, but rather stop at the
faulting frame.
Thus behaves as follow, _by default_:
<source>: In function 'int main()':
<source>:5:8: warning: dereference of NULL 'a' [CWE-476]
[-Wanalyzer-null-dereference]
5 | a->x = 4; /* Diagnostic would path should stop here rather than going
to shared_ptr_base.h */
| ~~~~~^~~
'int main()': events 1-2
|
| 4 | std::shared_ptr<A> a;
| | ^
| | |
| | (1) 'a' is NULL
| 5 | a->x = 4; /* Diagnostic path should stop here rather than going
to shared_ptr_base.h */
| | ~~~~~~~~
| | |
| | (2) dereference of NULL 'a'
|
A flag akin to -fanalyzer-trim-diagnostic-path=<maxdepth>|std would then be
introduced to do so, with a default value of std.
Such option would be useful for future support of C++, but could be extended to
any "system header", thus also be used in C.
A slight variation would be to trim all but the last exceeding event, so that
the user would still get feedback on template deducted types.
What do you think ?
