/* PR c/69002 */ /* Test we diagnose accessing elements of atomic structures or unions, which is undefined behavior (C11 6.5.2.3#5). */ /* { dg-do compile } */ /* { dg-options "-std=c11 -pedantic-errors" } */ struct S { int x; }; union U { int x; }; int fn1 (_Atomic struct S p) { int e = 0 && p.x; return p.x + e; /* { dg-warning "accessing a member .x. of an atomic structure" } */ } int fn2 (_Atomic struct S *p) { int e = 1 || p->x; return p->x + e; /* { dg-warning "accessing a member .x. of an atomic structure" } */ } void fn3 (_Atomic struct S p, int x) { p.x = x; /* { dg-warning "accessing a member .x. of an atomic structure" } */ } void fn4 (_Atomic struct S *p, int x) { p->x = x; /* { dg-warning "accessing a member .x. of an atomic structure" } */ } int fn5 (_Atomic struct S p) { /* This is OK: Members can be safely accessed using a non-atomic object which is assigned to or from the atomic object. */ struct S s = p; return s.x; } int fn6 (_Atomic struct S *p) { struct S s = *p; return s.x; } int fn7 (_Atomic union U p) { int e = 0 && p.x; return p.x + e; /* { dg-warning "accessing a member .x. of an atomic union" } */ } int fn8 (_Atomic union U *p) { int e = 1 || p->x; return p->x + e; /* { dg-warning "accessing a member .x. of an atomic union" } */ } void fn9 (_Atomic union U p, int x) { p.x = x; /* { dg-warning "accessing a member .x. of an atomic union" } */ } void fn10 (_Atomic union U *p, int x) { p->x = x; /* { dg-warning "accessing a member .x. of an atomic union" } */ } int fn11 (_Atomic union U p) { /* This is OK: Members can be safely accessed using a non-atomic object which is assigned to or from the atomic object. */ union U s = p; return s.x; } int fn12 (_Atomic union U *p) { union U s = *p; return s.x; }