Why is this an issue?

Certain mathematical comparisons will always return the same value, and should not be performed.

Specifically, the following comparisons will return either always true or always false depending on the kind of comparison:

comparing a char with a numeric constant that is outside of the range of char
comparing a float with a numeric constant that is outside of the range of float
comparing a long with a numeric constant that is outside of the range of long
comparing a ulong with a numeric constant that is outside of the range of ulong
etc.

float f = 42.0f;
if (f <= double.MaxValue) { } // Noncompliant: always true
if (f > double.MaxValue) { }  // Noncompliant: always false

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