Compiler Error CS0463

Evaluation of the decimal constant expression failed with error: 'error'

This errors occurs when a constant decimal expression overflows at compile time.

Typically you get overflow errors at run time. In this case, you defined the constant expression in such a way that the compiler could evaluate the result and know that an overflow would happen.

Example

The following code generates error CS0463.

// CS0463.cs
using System;
class MyClass
{  
    public static void Main()
    {  
        const decimal myDec = 79000000000000000000000000000.0m + 79000000000000000000000000000.0m; // CS0463  
        Console.WriteLine(myDec.ToString());  
    }  
}