1// run
2
3// Copyright 2018 The Go Authors. All rights reserved.
4// Use of this source code is governed by a BSD-style
5// license that can be found in the LICENSE file.
6
7// Issues 12576 and 12621: Negative untyped floating point constants
8// with small magnitude round to 0, not negative zero.
9
10package main
11
12import "math"
13
14var m = -1e-10000
15
16func main() {
17	if math.Signbit(m) {
18		panic(m)
19	}
20}
21