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/* { dg-do link } */
/* { dg-options "-O2" } */
struct S
{
int w, x, y, z;
};
struct T
{
int r;
struct S s;
};
void
foo (int a, struct T b)
{
struct S *c = 0;
if (a)
c = &b.s;
b.s.w = 3;
/* Since 'c' may be pointing to NULL here, we used to flag it as
pointing anywhere, which was forcing the aliaser to mark as
call-clobbered every other variable pointed-to by 'c' ('b' in
this case). This, in turn, caused the insertion of V_MAY_DEFs
for 'b' at this call-site, which prevented constant propagation
from 'b.s.w = 3' to 'if (b.s.w != 3)'. */
bar (*c, a);
if (b.s.w != 3)
link_error ();
}
int main ()
{
struct T b;
foo (3, b);
return 0;
}
int X;
int bar (struct S x, int i)
{
X = 3;
}
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