From 8425d558165e7eacf797d910f3509bc231abb084 Mon Sep 17 00:00:00 2001
From: "Steven G. Johnson" <stevenj@alum.mit.edu>
Date: Mon, 10 Nov 2014 12:32:11 -0500
Subject: [PATCH] fix #8968: abs(big(-0.0))

backport of a42a54bf5ba439850d4d78dc013c397e49cac79b
---
 base/number.jl  | 2 +-
 test/numbers.jl | 3 +++
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/base/number.jl b/base/number.jl
index ac4cee8c7f00b..85fd2506b30bc 100644
--- a/base/number.jl
+++ b/base/number.jl
@@ -21,7 +21,7 @@ last(x::Number) = x
 divrem(x,y) = (div(x,y),rem(x,y))
 signbit(x::Real) = x < 0
 sign(x::Real) = ifelse(x < 0, oftype(x,-1), ifelse(x > 0, one(x), x))
-abs(x::Real) = ifelse(x < 0, -x, x)
+abs(x::Real) = ifelse(signbit(x), -x, x)
 abs2(x::Real) = x*x
 copysign(x::Real, y::Real) = ifelse(signbit(x)!=signbit(y), -x, x)
 
diff --git a/test/numbers.jl b/test/numbers.jl
index 6a806033a09e8..2dbc193d2cb2f 100644
--- a/test/numbers.jl
+++ b/test/numbers.jl
@@ -1827,3 +1827,6 @@ ndigf(n) = float64(log(float32(n)))
 # issue #7911
 @test sum([int128(1) int128(2)]) == int128(3)
 
+let x = big(-0.0)
+    @test signbit(x) && !signbit(abs(x))
+end