const math/big.MaxExp

4 uses

	math/big (current package)
		float.go#L97: 	MaxExp  = math.MaxInt32  // largest supported exponent
		float.go#L291: 	if exp > MaxExp {
		float.go#L485: 				if z.exp >= MaxExp {
		floatconv.go#L123: 	if MinExp <= exp2 && exp2 <= MaxExp {