# V571. Recurring check. This condition was already verified in previous line.

The analyzer detected a potential error: one and the same condition is checked twice.

Consider two samples:

    // Example N1:
    if (A == B)
    {
      if (A == B)
        ...
    }

    // Example N2:
    if (A == B) {
    } else {
      if (A == B)
        ...
    }

In the first case, the second check "if (A==B)" is always true. In the second case, the second check is always false.

It is highly probable that this code has an error. For instance, a wrong variable name is used because of a misprint. This is the correct code:

    // Example N1:
    if (A == B)
    {
      if (A == C)
        ...
    }

    // Example N2:
    if (A == B) {
    } else {
      if (A == C)
        ...
    }

This diagnostic is classified as:

CWE-571

You can look at examples of errors detected by the V571 diagnostic.