incorrect type while define native value

[ltzmaxwell]

When defining Go native values, such as math.MinInt8, the introduced type is int, whereas it should be untyped int. this will cause a type check error(on type checker.)
ie.

package main

import "math"

func main() {
	var a int8 = 1
	println(a == math.MinInt8)
}

this happens when test xxx.native.