W8068 Constant out of range in comparison (C++)

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(Command-line option to suppress warning: -w-rng)

Your source file includes a comparison involving a constant sub-expression that was outside the range allowed by the other sub-expression's type.

For example, comparing an unsigned quantity to -1 makes no sense.

To get an unsigned constant greater than 32,767 (in decimal), you should either

• cast the constant to unsigned--for example, (unsigned) 65535, or
• append a letter u or U to the constant--for example, 65535u.

Whenever this message is issued, the compiler still generates code to do the comparison.

If this code ends up always giving the same result (such as comparing a char expression to 4000), the code will still perform the test.