1 // { dg-do run }
2 // { dg-options "-fno-strict-aliasing" }
3 // Origin: Mark Mitchell <mark@codesourcery.com>
4
5 /* Generally, the lowest bit of the ptr is used to indicate whether a
6 ptr-to-mem-func points to a virtual or a non-virtual member
7 function. However, some platforms use all bits to encode a
8 function pointer. Such platforms use the lowest bit of the delta,
9 that is shifted left by one bit. */
10 #if defined __MN10300__ || defined __SH5__ || defined __arm__ || defined __thumb__ || defined __mips__ || defined __aarch64__
11 #define ADJUST_PTRFN(func, virt) ((void (*)())(func))
12 #define ADJUST_DELTA(delta, virt) (((delta) << 1) + !!(virt))
13 #else
14 #define ADJUST_PTRFN(func, virt) ((void (*)())((ptrdiff_t)(func) + !!(virt)))
15 #define ADJUST_DELTA(delta, virt) (delta)
16 #endif
17
18 /* IA64 uses function descriptors instead of function pointers in its
19 vtables, which means that we can't meaningfully compare them directly. */
20 #if defined __ia64__
21 #define CMP_PTRFN(A, B) (*(void **)(A) == *(void **)(B))
22 #define VPTE_SIZE (16)
23 #else
24 #define CMP_PTRFN(A, B) ((A) == (B))
25 #define VPTE_SIZE sizeof(void *)
26 #endif
27
28 #if defined (__GXX_ABI_VERSION) && __GXX_ABI_VERSION >= 100
29
30 // Check that pointers-to-member functions are represented correctly.
31
32 #include <cstddef>
33
34 struct S
35 {
36 int i;
37 int j;
38 };
39
40 // Because S does not have a VPTR, it will not be a primary base of T,
41 // and will therefore end up at a nonzero offset.
42
43 struct T : public S
44 {
fT45 void f () {}
gT46 virtual void g () {}
hT47 virtual void h () {}
48 };
49
50 // Provide access to the raw function pointers. This is
51 // mangling-dependent.
52
53 extern "C" void _ZN1T1fEv ();
54 extern "C" void _ZN1T1gEv ();
55 extern "C" void _ZN1T1hEv ();
56
57 // This structure is a C representation of a pointer-to-member.
58
59 struct ptrmemfunc
60 {
61 void (*ptr) ();
62 ptrdiff_t adj;
63 };
64
65 typedef int S::*sdp;
66 typedef void (S::*sp)();
67 typedef void (T::*tp)();
68
69 int
main()70 main ()
71 {
72 S s;
73 T t;
74 sp x;
75 tp y;
76 ptrmemfunc *xp = (ptrmemfunc *) &x;
77 ptrmemfunc *yp = (ptrmemfunc *) &y;
78 ptrdiff_t delta = ((char *) &t) - ((char*) (S*) (&t));
79
80 // Pointers-to-function-members should have the same size and
81 // alignment as the PTRMEMFUNC type.
82 if (sizeof (sp) != sizeof (ptrmemfunc))
83 return 1;
84 if (__alignof__ (sp) != __alignof__ (ptrmemfunc))
85 return 2;
86
87 // The NULL pointer-to-member should have a NULL first PTR field.
88 x = 0;
89 if (xp->ptr != 0)
90 return 3;
91 y = x;
92 if (yp->ptr != 0)
93 return 4;
94
95 // A non-virtual function should have a pointer to the function.
96 // There should be no adjustment for the `T' version, and an
97 // appropriate adjustment for the `S' version.
98 y = &T::f;
99 if (! CMP_PTRFN (yp->ptr, ADJUST_PTRFN (&_ZN1T1fEv, 0)))
100 return 5;
101 if (yp->adj != ADJUST_DELTA (0, 0))
102 return 6;
103 x = (sp) y;
104 if (! CMP_PTRFN (xp->ptr, ADJUST_PTRFN (&_ZN1T1fEv, 0)))
105 return 7;
106 if (xp->adj != ADJUST_DELTA (delta, 0))
107 return 8;
108
109 // For a virtual function, we should see the vtable offset, plus
110 // one. `T::h' is in the second slot: the vtable pointer points to
111 // the first virtual function.
112 y = &T::h;
113 if (yp->ptr != ADJUST_PTRFN (VPTE_SIZE, 1))
114 return 9;
115 if (yp->adj != ADJUST_DELTA (0, 1))
116 return 10;
117 x = (sp) y;
118 if (xp->ptr != ADJUST_PTRFN (VPTE_SIZE, 1))
119 return 11;
120 if (xp->adj != ADJUST_DELTA (delta, 1))
121 return 12;
122
123 // Pointers-to-data-members should have the same size and alignment
124 // as a ptrdiff_t.
125 if (sizeof (sdp) != sizeof (ptrdiff_t))
126 return 13;
127 if (__alignof__ (sdp) != __alignof__ (ptrdiff_t))
128 return 14;
129
130 // The value of a pointer-to-data member should be the offset from
131 // the start of the structure.
132 sdp z = &S::j;
133 if ((char *) &s.j - (char *) &s != *((ptrdiff_t *) &z))
134 return 15;
135 z = 0;
136 if (*((ptrdiff_t *) &z) != -1)
137 return 16;
138 }
139
140 #else /* !(defined (__GXX_ABI_VERSION) && __GXX_ABI_VERSION >= 100) */
141
main()142 int main ()
143 {
144 }
145
146 #endif /* !(defined (__GXX_ABI_VERSION) && __GXX_ABI_VERSION >= 100) */
147