by juanval:

go version go1.3 darwin/amd64

What steps reproduce the problem?
Example: http://play.golang.org/p/-GqZSloAM3

    1. fmt.Println(math.Sin(1.5e17))

What happened?

    Program prints "1.231298118089368e+08"

What should have happened instead?

    Program should print value in [-1,1] range

Please provide any additional information below.

    Source code for math.Sin warns that "Results may be meaningless for x > 2**49 = 5.6e14". However, it says nothing about not respecting the [-1,1] range. 

    I discovered this when doing math.Sin(float64(time.Now().UnixNano())) returned 1.1828933275348654e+20

    Also, that information does not appear in godoc.