https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98406
Bug ID: 98406
Summary: missing -Wmaybe-uninitialized passing a member by
reference
Product: gcc
Version: 11.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: middle-end
Assignee: unassigned at gcc dot gnu.org
Reporter: msebor at gcc dot gnu.org
Target Milestone: ---
In the test case below, only the first (likely) uninitialized read by f() is
diagnosed. The other two are not even though all three should be.
$ cat a.c && gcc -O2 -S -Wall a.c
int f (const int*);
struct A { int i; };
struct B { struct A a; int j; };
void g0 (void)
{
struct B b;
f (&b.j); // warning (good)
}
void g1 (void)
{
struct B b;
f (0);
f (&b.j); // missing warning
}
void g2 (void)
{
struct B b;
b.a.i = 0;
f (&b.a.i);
f (&b.j); // missing warning
}
a.c: In function ‘g0’:
a.c:9:3: warning: ‘b’ may be used uninitialized [-Wmaybe-uninitialized]
9 | f (&b.j); // warning (good)
| ^~~~~~~~
a.c:1:5: note: by argument 1 of type ‘const int *’ to ‘f’ declared here
1 | int f (const int*);
| ^
a.c:8:12: note: ‘b’ declared here
8 | struct B b;
| ^
