https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104415
Bug ID: 104415
Summary: uninit diagnostic improvement at -O0
Product: gcc
Version: 12.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: tree-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: rguenth at gcc dot gnu.org
Target Milestone: ---
For
int foo ()
{
int cond = 1;
int tem;
return cond ? tem : 0;
}
we emit
t.c: In function 'foo':
t.c:5:21: warning: 'tem' may be used uninitialized [-Wmaybe-uninitialized]
5 | return cond ? tem : 0;
| ~~~~~~~~~~~^~~
t.c:4:7: note: 'tem' was declared here
4 | int tem;
| ^~~
when not optimizing but
t.c: In function 'foo':
t.c:5:21: warning: 'tem' is used uninitialized [-Wuninitialized]
5 | return cond ? tem : 0;
| ~~~~~~~~~~~^~~
t.c:4:7: note: 'tem' was declared here
4 | int tem;
| ^~~
when optimizing. Even when not optimizing we could figure out the condition
is constant and emit the "is used uninitialized" variant.
