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// { dg-do run }
// Copyright (C) 2001 Free Software Foundation, Inc.
// Contributed by Nathan Sidwell 31 Jul 2001 <nathan@codesourcery.com>
// Bug 3820. We were bit copying empty bases including the
// padding. Which clobbers whatever they overlay.
struct Empty {};
struct Inter : Empty {};
long now = 0;
struct NonPod
{
long m;
NonPod () {m = 0x12345678;}
NonPod (long m_) {m = m_;}
NonPod &operator= (NonPod const &src) {now = m; m = src.m; return *this;}
NonPod (NonPod const &src) {m = src.m;}
};
struct A : Inter
{
A (long c) {m = c;}
NonPod m;
};
struct B
{
Inter empty;
NonPod m;
B (long c) {m = c;}
};
#if __cpp_attributes
struct B2
{
[[no_unique_address]] Inter empty;
NonPod m;
B2 (long c) {m = c;}
};
#endif
struct C : NonPod, Inter
{
C (long c) : NonPod (c), Inter () {}
};
int main ()
{
A a (0x12131415);
long was = a.m.m;
a = 0x22232425;
if (was != now)
return 1; // we copied the empty base which clobbered a.m.m's
// original value.
A b (0x32333435);
*(Inter *)&a = *(Inter *)&b;
if (a.m.m != 0x22232425)
return 2; // we copied padding, which clobbered a.m.m
A b2 (0x32333435);
(Inter &)b2 = Inter ();
if (b2.m.m != 0x32333435)
return 2; // we copied padding, which clobbered b2.m.m
{
B c (0x12131415);
was = c.m.m;
c = 0x22232425;
if (was != now)
return 3;
B d (0x32333435);
c.empty = d.empty;
if (c.m.m != 0x22232425)
return 4;
}
#if __cpp_attributes
{
B2 c (0x12131415);
was = c.m.m;
c = 0x22232425;
if (was != now)
return 3;
B2 d (0x32333435);
c.empty = d.empty;
if (c.m.m != 0x22232425)
return 4;
}
#endif
C e (0x32333435);
if (e.m != 0x32333435)
return 2; // we copied padding
return 0;
}
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