|  | // run | 
|  |  | 
|  | // Copyright 2012 The Go Authors. All rights reserved. | 
|  | // Use of this source code is governed by a BSD-style | 
|  | // license that can be found in the LICENSE file. | 
|  |  | 
|  | // Test that typed and untyped negative zero floating point constants | 
|  | // are treated as equivalent to zero constants. | 
|  |  | 
|  | package main | 
|  |  | 
|  | import "math" | 
|  |  | 
|  | const zero = 0.0 | 
|  |  | 
|  | func main() { | 
|  | x := -zero | 
|  | b := math.Float64bits(x) | 
|  | if b != 0 { | 
|  | panic(b) | 
|  | } | 
|  | x = -float64(zero) | 
|  | b = math.Float64bits(x) | 
|  | if b != 0 { | 
|  | panic(b) | 
|  | } | 
|  | v := x | 
|  | b = math.Float64bits(-v) | 
|  | if b != 0x8000000000000000 { | 
|  | panic(b) | 
|  | } | 
|  | } |