func runtime.copysign

4 uses

	runtime (current package)
		complex.go#L14: 	return copysign(g, f)
		complex.go#L43: 			e = copysign(inf, c) * a
		complex.go#L44: 			f = copysign(inf, c) * b
		float.go#L39: func copysign(x, y float64) float64 {