libgo: update to final Go 1.8 release

    
    Along with the update this fixes a problem that was always present but
    only showed up with the new reflect test.  When a program used a
    **unsafe.Pointer and stored the value in an interface type, the
    generated type descriptor pointed to the GC data for *unsafe.Pointer.
    It did that by name, but we were not generating a variable with the
    right name.
    
    Reviewed-on: https://go-review.googlesource.com/37144

From-SVN: r245535

2 files changed, 11 insertions, 3 deletions

diff --git a/libgo/go/reflect/all_test.go b/libgo/go/reflect/all_test.go
index 6b143df..859de7c 100644
--- a/libgo/go/reflect/all_test.go
+++ b/libgo/go/reflect/all_test.go
@@ -2481,17 +2481,24 @@ func TestNumMethodOnDDD(t *testing.T) {
 }
 
 func TestPtrTo(t *testing.T) {
+	// This block of code means that the ptrToThis field of the
+	// reflect data for *unsafe.Pointer is non zero, see
+	// https://golang.org/issue/19003
+	var x unsafe.Pointer
+	var y = &x
+	var z = &y
+
 	var i int
 
-	typ := TypeOf(i)
+	typ := TypeOf(z)
 	for i = 0; i < 100; i++ {
 		typ = PtrTo(typ)
 	}
 	for i = 0; i < 100; i++ {
 		typ = typ.Elem()
 	}
-	if typ != TypeOf(i) {
-		t.Errorf("after 100 PtrTo and Elem, have %s, want %s", typ, TypeOf(i))
+	if typ != TypeOf(z) {
+		t.Errorf("after 100 PtrTo and Elem, have %s, want %s", typ, TypeOf(z))
 	}
 }
 
diff --git a/libgo/go/reflect/type.go b/libgo/go/reflect/type.go
index 29d89f7..0325260 100644
--- a/libgo/go/reflect/type.go
+++ b/libgo/go/reflect/type.go
@@ -1174,6 +1174,7 @@ func (t *rtype) ptrTo() *rtype {
 	pp := *prototype
 
 	pp.string = &s
+	pp.ptrToThis = nil
 
 	// For the type structures linked into the binary, the
 	// compiler provides a good hash of the string.