# V3182. The result of '&' operator is always '0'.

The analyzer has detected the use of bitwise 'AND' (&) with operands that always make the result of the operation equal to 0. A code fragment may contain incorrect operator or operand.

Example:

    public enum FlagType : ulong
    {
      Package = 1 << 1,
      Import = 1 << 2,
      Namespace = 1 << 3,
      ....
    }
    ....
    FlagType bitMask = FlagType.Package & FlagType.Import;

Here, 'bitMask' is the 'FlagType' enumeration type object in which the bit mask is created.

This method of combining enumeration flags is incorrect. Bitwise 'AND' (&) between the 'FlagType.Package' and 'FlagType.Import' values are equal to zero, since these bit flags do not contain ones in the corresponding bits.

The correct implementation of combining flags may look as follows:

    FlagType bitMask = FlagType.Package | FlagType.Import;

This diagnostic is classified as:

CWE-480

You can look at examples of errors detected by the V3182 diagnostic.