libgo: update to Go1.10beta1

    
    Update the Go library to the 1.10beta1 release.
    
    Requires a few changes to the compiler for modifications to the map
    runtime code, and to handle some nowritebarrier cases in the runtime.
    
    Reviewed-on: https://go-review.googlesource.com/86455

gotools/:
	* Makefile.am (go_cmd_vet_files): New variable.
	(go_cmd_buildid_files, go_cmd_test2json_files): New variables.
	(s-zdefaultcc): Change from constants to functions.
	(noinst_PROGRAMS): Add vet, buildid, and test2json.
	(cgo$(EXEEXT)): Link against $(LIBGOTOOL).
	(vet$(EXEEXT)): New target.
	(buildid$(EXEEXT)): New target.
	(test2json$(EXEEXT)): New target.
	(install-exec-local): Install all $(noinst_PROGRAMS).
	(uninstall-local): Uninstasll all $(noinst_PROGRAMS).
	(check-go-tool): Depend on $(noinst_PROGRAMS).  Copy down
	objabi.go.
	(check-runtime): Depend on $(noinst_PROGRAMS).
	(check-cgo-test, check-carchive-test): Likewise.
	(check-vet): New target.
	(check): Depend on check-vet.  Look at cmd_vet-testlog.
	(.PHONY): Add check-vet.
	* Makefile.in: Rebuild.

From-SVN: r256365

2 files changed, 196 insertions, 0 deletions

diff --git a/libgo/go/container/heap/heap_test.go b/libgo/go/container/heap/heap_test.go
index d41110422e9..f19f9cfa74b 100644
--- a/libgo/go/container/heap/heap_test.go
+++ b/libgo/go/container/heap/heap_test.go
@@ -33,6 +33,7 @@ func (h *myHeap) Push(v interface{}) {
 }
 
 func (h myHeap) verify(t *testing.T, i int) {
+	t.Helper()
 	n := h.Len()
 	j1 := 2*i + 1
 	j2 := 2*i + 2
diff --git a/libgo/go/container/ring/example_test.go b/libgo/go/container/ring/example_test.go
new file mode 100644
index 00000000000..d8f16390eef
--- /dev/null
+++ b/libgo/go/container/ring/example_test.go
@@ -0,0 +1,195 @@
+// Copyright 2017 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.
+
+// +build ignore
+
+package ring_test
+
+import (
+	"container/ring"
+	"fmt"
+)
+
+func ExampleRing_Len() {
+	// Create a new ring of size 4
+	r := ring.New(4)
+
+	// Print out its length
+	fmt.Println(r.Len())
+
+	// Output:
+	// 4
+}
+
+func ExampleRing_Next() {
+	// Create a new ring of size 5
+	r := ring.New(5)
+
+	// Get the length of the ring
+	n := r.Len()
+
+	// Initialize the ring with some integer values
+	for i := 0; i < n; i++ {
+		r.Value = i
+		r = r.Next()
+	}
+
+	// Iterate through the ring and print its contents
+	for j := 0; j < n; j++ {
+		fmt.Println(r.Value)
+		r = r.Next()
+	}
+
+	// Output:
+	// 0
+	// 1
+	// 2
+	// 3
+	// 4
+}
+
+func ExampleRing_Prev() {
+	// Create a new ring of size 5
+	r := ring.New(5)
+
+	// Get the length of the ring
+	n := r.Len()
+
+	// Initialize the ring with some integer values
+	for i := 0; i < n; i++ {
+		r.Value = i
+		r = r.Next()
+	}
+
+	// Iterate through the ring backwards and print its contents
+	for j := 0; j < n; j++ {
+		r = r.Prev()
+		fmt.Println(r.Value)
+	}
+
+	// Output:
+	// 4
+	// 3
+	// 2
+	// 1
+	// 0
+}
+
+func ExampleRing_Do() {
+	// Create a new ring of size 5
+	r := ring.New(5)
+
+	// Get the length of the ring
+	n := r.Len()
+
+	// Initialize the ring with some integer values
+	for i := 0; i < n; i++ {
+		r.Value = i
+		r = r.Next()
+	}
+
+	// Iterate through the ring and print its contents
+	r.Do(func(p interface{}) {
+		fmt.Println(p.(int))
+	})
+
+	// Output:
+	// 0
+	// 1
+	// 2
+	// 3
+	// 4
+}
+
+func ExampleRing_Move() {
+	// Create a new ring of size 5
+	r := ring.New(5)
+
+	// Get the length of the ring
+	n := r.Len()
+
+	// Initialize the ring with some integer values
+	for i := 0; i < n; i++ {
+		r.Value = i
+		r = r.Next()
+	}
+
+	// Move the pointer forward by three steps
+	r = r.Move(3)
+
+	// Iterate through the ring and print its contents
+	r.Do(func(p interface{}) {
+		fmt.Println(p.(int))
+	})
+
+	// Output:
+	// 3
+	// 4
+	// 0
+	// 1
+	// 2
+}
+
+func ExampleRing_Link() {
+	// Create two rings, r and s, of size 2
+	r := ring.New(2)
+	s := ring.New(2)
+
+	// Get the length of the ring
+	lr := r.Len()
+	ls := s.Len()
+
+	// Initialize r with 0s
+	for i := 0; i < lr; i++ {
+		r.Value = 0
+		r = r.Next()
+	}
+
+	// Initialize s with 1s
+	for j := 0; j < ls; j++ {
+		s.Value = 1
+		s = s.Next()
+	}
+
+	// Link ring r and ring s
+	rs := r.Link(s)
+
+	// Iterate through the combined ring and print its contents
+	rs.Do(func(p interface{}) {
+		fmt.Println(p.(int))
+	})
+
+	// Output:
+	// 0
+	// 0
+	// 1
+	// 1
+}
+
+func ExampleRing_Unlink() {
+	// Create a new ring of size 6
+	r := ring.New(6)
+
+	// Get the length of the ring
+	n := r.Len()
+
+	// Initialize the ring with some integer values
+	for i := 0; i < n; i++ {
+		r.Value = i
+		r = r.Next()
+	}
+
+	// Unlink three elements from r, starting from r.Next()
+	r.Unlink(3)
+
+	// Iterate through the remaining ring and print its contents
+	r.Do(func(p interface{}) {
+		fmt.Println(p.(int))
+	})
+
+	// Output:
+	// 0
+	// 4
+	// 5
+}