| // 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) | 
 | 	} | 
 | } |