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This noncompliant code example appears to have five iterations, but in fact, the loop never terminates.:

size_t i;
for (i = 1; i != 10; i += 2) {
  /* ... */
}

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Using the relational operator <= instead of an equality operator guarantees loop termination.:

size_t i;
for (i = 1; i <= 10; i += 2 ) {
  /* ... */
}

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It is also important to ensure termination of loops where the start and end values are variables that might not be properly ordered. The following function assumes that begin < end; if this is not the case, the loop will never terminate.:

void f(size_t begin, size_t end) {
  size_t i;
  for (i = begin; i != end; ++i) {
    /* ... */
  }
}

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A compliant solution is to compare against the difference between the maximum representable value of a type and the increment.:

void f(size_t begin, size_t step) {
  if (0 < step) {
    int i;
    for (i = begin; i <= INT_MAX - step; i += step) {
      /* ... */
    }
  }
}

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