1 files changed, 102 insertions, 0 deletions
diff --git a/test/fixedbugs/issue27718.go b/test/fixedbugs/issue27718.go
new file mode 100644
index 0000000..ff616fb
--- /dev/null
+++ b/test/fixedbugs/issue27718.go
@@ -0,0 +1,102 @@
+// run
+
+// Copyright 2018 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.
+
+// (-0)+0 should be 0, not -0.
+
+package main
+
+//go:noinline
+func add64(x float64) float64 {
+	return x + 0
+}
+
+func testAdd64() {
+	var zero float64
+	inf := 1.0 / zero
+	negZero := -1 / inf
+	if 1/add64(negZero) != inf {
+		panic("negZero+0 != posZero (64 bit)")
+	}
+}
+
+//go:noinline
+func sub64(x float64) float64 {
+	return x - 0
+}
+
+func testSub64() {
+	var zero float64
+	inf := 1.0 / zero
+	negZero := -1 / inf
+	if 1/sub64(negZero) != -inf {
+		panic("negZero-0 != negZero (64 bit)")
+	}
+}
+
+//go:noinline
+func neg64(x float64) float64 {
+	return -x
+}
+
+func testNeg64() {
+	var zero float64
+	inf := 1.0 / zero
+	negZero := -1 / inf
+	if 1/neg64(negZero) != inf {
+		panic("-negZero != posZero (64 bit)")
+	}
+}
+
+//go:noinline
+func add32(x float32) float32 {
+	return x + 0
+}
+
+func testAdd32() {
+	var zero float32
+	inf := 1.0 / zero
+	negZero := -1 / inf
+	if 1/add32(negZero) != inf {
+		panic("negZero+0 != posZero (32 bit)")
+	}
+}
+
+//go:noinline
+func sub32(x float32) float32 {
+	return x - 0
+}
+
+func testSub32() {
+	var zero float32
+	inf := 1.0 / zero
+	negZero := -1 / inf
+	if 1/sub32(negZero) != -inf {
+		panic("negZero-0 != negZero (32 bit)")
+	}
+}
+
+//go:noinline
+func neg32(x float32) float32 {
+	return -x
+}
+
+func testNeg32() {
+	var zero float32
+	inf := 1.0 / zero
+	negZero := -1 / inf
+	if 1/neg32(negZero) != inf {
+		panic("-negZero != posZero (32 bit)")
+	}
+}
+
+func main() {
+	testAdd64()
+	testSub64()
+	testNeg64()
+	testAdd32()
+	testSub32()
+	testNeg32()
+}