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152
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1 /* { dg-do run } */
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2
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3 struct list { struct list *n; };
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4
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5 struct obj {
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6 int n;
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7 struct list l;
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8 } _o;
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9
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10 struct list _l = { .n = &_o.l };
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11
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12 int main(int argc, char *argv[])
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13 {
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14 struct obj *o = &_o;
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15 _o.l.n = &_l;
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16 while (&o->l != &_l)
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17 /* Note the following is invoking undefined behavior but in
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18 this kind of "obvious" cases we don't want to break things
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19 unnecessarily and thus we avoid analyzing o as pointing
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20 to nothing via the undefined pointer subtraction. Instead
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21 we canonicalize the pointer subtraction followed by the
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22 pointer conversion to pointer offsetting. */
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23 o = ((struct obj *)((const char *)(o->l.n)
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24 - (const char *)&((struct obj *)0)->l));
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25 return 0;
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26 }
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