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In this noncompliant code example, assignments between restricted pointers in the file scope declarations assert that if an object is accessed using one of a, b, or c, and that object is modified anywhere in the program, then it is never accessed using either of the other twosame scope is disallowed.

int * restrict a;
int * restrict b;

extern int c[];
 
int main(void) {
  c[0] = 17; 
  c[1] = 18;
  a = &c[0]; 
  b = &c[1];
  *a = *b; /* undefined behavior */

  ...
}

Compliant Solution

One way to eliminate the undefined behavior is simply to remove the restrict-qualification from the affected pointers. 

int * a;
int * b;

extern int c[];
 
int main(void) {
  c[0] = 17; 
  c[1] = 18;
  a = &c[0]; 
  b = &c[1];
  *a = *b; /* valid defined behavior */

  ...
}

restrict-qualified pointers Function Parameters

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