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1 // { dg-do run  }
2 // { dg-options "-fno-strict-aliasing" }
3 // Origin: Mark Mitchell <mark@codesourcery.com>
4 
5 #if defined (__GXX_ABI_VERSION) && __GXX_ABI_VERSION >= 100
6 
7 #include <stddef.h>
8 
9 struct S0
10 {
11   virtual void s0 ();
12 };
13 
14 struct S1 : virtual public S0
15 {
16   virtual void s1 ();
17 };
18 
19 struct S2 : virtual public S1
20 {
21   virtual void s1 ();
22   virtual void s0 ();
23 };
24 
25 struct S3
26 {
27   virtual void s3 ();
28 };
29 
30 struct S4 : public S3, virtual public S2
31 {
32   virtual void s1 ();
33 };
34 
s0()35 void S0::s0 ()
36 {
37 }
38 
s1()39 void S1::s1 ()
40 {
41 }
42 
s1()43 void S2::s1 ()
44 {
45 }
46 
s0()47 void S2::s0 ()
48 {
49 }
50 
s3()51 void S3::s3 ()
52 {
53 }
54 
s1()55 void S4::s1 ()
56 {
57 }
58 
59 /* The vtables should look like:
60 
61    S0 primary vtable
62 
63      S0 offset to top
64      S0 RTTI
65      S0::s0
66 
67    =================
68 
69    S1 primary vtable
70 
71      S0::s0 vcall offset
72      S0 vbase offset
73      S1 offset to top
74      S1 RTTI
75      S0::s0
76      S1::s1
77 
78    =================
79 
80    S2 primary vtable
81 
82      S2::s1 vcall offset
83      S1 vbase offset
84      S2::s0 vcall offset
85      S0 vbase offset
86      S2 offset to top
87      S2 RTTI
88      S2::s0
89      S2::s1
90 
91    =================
92 
93    S3 primary vtable
94 
95      S3 offset to top
96      S3 RTTI
97      S3::s3
98 
99    =================
100 
101    S4 primary vtable
102 
103      vbase offset for S0
104      vbase offset for S1
105      vbase offset for S2
106      S4 offset to top
107      S4 RTTI
108      S3::s3
109      S4::s1
110 
111    S2-in-S4 secondary vtable
112 
113      S1 vbase offset
114      S4::s1 vcall offset
115      S0 vbase offset
116      S2:s0 vcall offset
117      S2 offset to top
118      S4 RTTI
119      S2::s0
120      S4::s1
121 
122 */
123 
124 // These are tricks to allow us to get raw function pointers for
125 // member functions.
126 extern "C" {
127   /* We can use weakref here without dg-require-weak, because we know
128      the symbols are defined, so we don't actually issue the .weak
129      directives.  */
130   static void S3_s3 () __attribute__((__weakref__ ("_ZN2S32s3Ev")));
131   static void S4_s1 () __attribute__((__weakref__ ("_ZN2S42s1Ev")));
132 }
133 
134 // IA-64 uses function descriptors not function pointers in its vtables.
135 #if defined __ia64__
136 #define CMP_VPTR(A, B)	(*(void **)(A) == *(void **)(B))
137 #ifdef _LP64
138 #define INC_VPTR(A)	((A) += 2)
139 #define INC_VDATA(A,N)	((A) += (N))
140 #else
141 #define INC_VPTR(A)	((A) += 4)
142 #define INC_VDATA(A,N)	((A) += 2*(N))
143 #endif
144 #else
145 #define CMP_VPTR(A, B)	(*(A) == (ptrdiff_t)(B))
146 #define INC_VPTR(A)	((A) += 1)
147 #define INC_VDATA(A,N)	((A) += (N))
148 #endif
149 
main()150 int main ()
151 {
152   S4 s4;
153   ptrdiff_t **vptr;
154   ptrdiff_t *vtbl;
155 
156   // Set vtbl to point at the beginning of S4's primary vtable.
157   vptr = (ptrdiff_t **) &s4;
158   vtbl = *vptr;
159   INC_VDATA (vtbl, -5);
160 
161   if (*vtbl != ((char*) (S0*) &s4) - (char*) &s4)
162     return 1;
163   INC_VDATA (vtbl, 1);
164   if (*vtbl != ((char*) (S1*) &s4) - (char*) &s4)
165     return 2;
166   INC_VDATA (vtbl, 1);
167   if (*vtbl != ((char*) (S2*) &s4) - (char*) &s4)
168     return 3;
169   INC_VDATA (vtbl, 1);
170   if (*vtbl != 0)
171     return 4;
172   INC_VDATA (vtbl, 1);
173   // Skip the RTTI entry.
174   INC_VDATA (vtbl, 1);
175   if (! CMP_VPTR (vtbl, &S3_s3))
176     return 5;
177   INC_VPTR (vtbl);
178   if (! CMP_VPTR (vtbl, &S4_s1))
179     return 6;
180   INC_VPTR (vtbl);
181   // The S1 vbase offset.
182   if (*vtbl != 0)
183     return 7;
184   INC_VDATA (vtbl, 1);
185   // The S4::s1 vcall offset is negative; once you convert to S2, you
186   // have to convert to S4 to find the final overrider.
187   if (*vtbl != ((char*) &s4 - (char*) (S2*) &s4))
188     return 8;
189   INC_VDATA (vtbl, 1);
190   if (*vtbl != 0)
191     return 9;
192   INC_VDATA (vtbl, 1);
193   if (*vtbl != 0)
194     return 10;
195   INC_VDATA (vtbl, 1);
196   // Now we're at the S2 offset to top entry.
197   if (*vtbl != ((char*) &s4 - (char*) (S2*) &s4))
198     return 11;
199   INC_VDATA (vtbl, 1);
200   // Skip the RTTI entry.
201   INC_VDATA (vtbl, 1);
202   // Skip the reint maining virtual functions -- they are thunks.
203   INC_VPTR (vtbl);
204   INC_VPTR (vtbl);
205 }
206 
207 #else /* !(defined (__GXX_ABI_VERSION) && __GXX_ABI_VERSION >= 100) */
208 
main()209 int main ()
210 {
211 }
212 
213 #endif /* !(defined (__GXX_ABI_VERSION) && __GXX_ABI_VERSION >= 100) */
214