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/*
** tests aliasing of arrays, structs and unions
*/
# include "alias3.lh"
st gst;
ut *gu;
void model (int ia[])
{
int *ip;
ip = &(ia[6]);
*ip = 3;
gst.a = 3; /* 1. Suspect modification of gst.a */
gu->a = 5; /* 2. Suspect modification of gu->a */
}
void modst (st s1)
{
s1.a = 3;
*(s1.b) = 6;
}
void modu (ut *u)
{
u->a = 5;
}
int f (int ia[], st s1, ut *u1)
{
int *ip;
st sl;
ut *ul;
ip = &(ia[3]);
*ip = 7; /* modifies ia[3] */
ip = &(ia[*ip]);
*ip = 8; /* modifies ia[?] */
model(ia); /* modifies ia[6] */
ip = ia;
model(ip); /* modifies ia[6] */
s1.a = 3; /* okay */
*(s1.b) = 7; /* modifies *(s1.b) */
sl = s1; /* okay (sl is NOT an alias for s1) */
modst(sl); /* was: does not modify anything --- structure is passed by value */
/* NOT TRUE: does modify sl since *s1.b is the same reference */
sl.a = 3; /* okay */
ip = s1.b; /* okay, ip aliases s1.b */
*(s1.b) = 3; /* modifies s1.b */
*ip = 6; /* modifies s1.b */
*(sl.b) = 3; /* okay */
ul = u1; /* ul aliases u1 */
modu(ul); /* okay */
ul->a = 3; /* modifies u1->a */
sl = ul->s; /* okay */
sl.a = 3; /* okay */
*(sl.b) = 6; /* modifies *(u1->s.b) through alias */
return 5;
}
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