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int array[]; // may be null
int i;       // may be a valid index for array
if (data array!= null) {
  if (i >= 0 & i < dataarray.length) {
    if (dataarray[i] != -1) {
      // use array
    } else {
      // handle error
    }
  } else {
    // handle error
  }
} else {
  // handle error
}

Nevertheless, this solution is preferable if the error-handling routines code for each potential condition failure were different.

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The problem with this code is that when the first condition in the while loop fails, the second condition is not executed. That is, once i1 has reached array1.length, the loop could will terminate after i1 is executedincremented. Consequently, the apparent range over array1 is larger than the apparent range over array2, causing the final assertion to fail.

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  while (++i1 < array1.length &     // not &&
         ++i2 < array2.length &&
         array1[i1] == array2[i2])

Compliant Solution (Nested if Statements)

This compliant solution uses multiple if statements to achieve the proper effect. Although correct, it is more verbose.

  while (true) {
    if (++i1 >= array1.length) break;
    if (++i2 >= array2.length) break;
    if (array1[i1] != array2[i2]) break;
    // rest of loop
  }

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Applicability

Failure to understand the behavior of the bitwise and conditional operators can cause unintended program behavior.

Related Guidelines

CERT C Secure Coding Standard: EXP02-C. Be aware of the short-circuit behavior of the logical AND and OR operators
CERT C++ Secure Coding Standard: EXP02-CPP. Be aware of the short-circuit behavior of the logical AND and OR operators

Bibliography

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