https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101836
Bug ID: 101836
Summary: __builtin_object_size(P->M, 1) where M is an array and
the last member of a struct fails
Product: gcc
Version: unknown
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c
Assignee: unassigned at gcc dot gnu.org
Reporter: kees at outflux dot net
Target Milestone: ---
Created attachment 51282
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=51282&action=edit
struct layout changes bos1 behavior
When bos1 is used on a member who is both an array and at the end of a
structure, it fails to correctly resolve. This kind of behavior should only
happen for flexible array members:
struct trailing_array {
int a;
int b;
unsigned char c[16];
};
struct middle_array {
int a;
unsigned char c[16];
int b;
};
ok: sizeof(*working) == 24
ok: sizeof(working->c) == 16
ok: __builtin_object_size(working, 1) == -1
ok: __builtin_object_size(working->c, 1) == 16
ok: sizeof(*broken) == 24
ok: sizeof(broken->c) == 16
ok: __builtin_object_size(broken, 1) == -1
WAT: __builtin_object_size(broken->c, 1) == -1 (expected 16)
