https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95240
Bug ID: 95240
Summary: calloc() false positives
Product: gcc
Version: 10.1.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: analyzer
Assignee: dmalcolm at gcc dot gnu.org
Reporter: gcc.gnu.org at andred dot net
Target Milestone: ---
Host: x86_64-linux-gnu
Target: x86_64-linux-gnu
Build: x86_64-linux-gnu
Created attachment 48574
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=48574&action=edit
testcase
Test with: gcc-10 (Debian 10.1.0-2) 10.1.0
(same behaviour with gcc 10.0)
With the attached, I get a false positive:
gcc-10 -Os -fanalyzer -fdiagnostics-path-format=separate-events t.c -o t
t.c: In function ‘initActiveTroubleArray’:
t.c:13:35: warning: leak of ‘<unknown>’ [CWE-401] [-Wanalyzer-malloc-leak]
13 | return activeTroubleArray ? 0 : 1;
| ~~~~~~~~~~~~~~~~~~~~~~~^~~
t.c:12:26: note: (1) allocated here
12 | activeTroubleArray = calloc (1, 1);
| ^~~~~~~~~~~~~
t.c:13:35: note: (2) ‘<unknown>’ leaks here; was allocated at (1)
13 | return activeTroubleArray ? 0 : 1;
| ~~~~~~~~~~~~~~~~~~~~~~~^~~
The warning goes away in either of the following cases:
* use malloc() instead of calloc() and change nothing else
* remove the test in initActiveTroubleArray() and change nothing else
* declare activeTroubleArray as void * and change nothing else (note that the
warning is triggered when using anything but void * - standard types like char,
long, etc, but also when using struct, enum etc.)
