From: Keith Randall <khr@golang.org>
Date: Mon, 8 Nov 2021 05:29:30 +0000 (-0800)
Subject: internal/fmtsort: order channels in test in memory address order
X-Git-Tag: go1.18beta1~455
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=6a9d81174e6c7d205fc189a1eac56212a723c40c;p=gostls13.git

internal/fmtsort: order channels in test in memory address order

Kind of a kludge, but it makes the test work reliably.

Fixes #49431

Change-Id: Ic2a075ba02f80ea7efcc1b3f0f5a43649e87c0d8
Reviewed-on: https://go-review.googlesource.com/c/go/+/361918
Trust: Keith Randall <khr@golang.org>
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
---

diff --git a/src/internal/fmtsort/sort_test.go b/src/internal/fmtsort/sort_test.go
index 5c4db1c5fa..ab063af5ba 100644
--- a/src/internal/fmtsort/sort_test.go
+++ b/src/internal/fmtsort/sort_test.go
@@ -9,6 +9,7 @@ import (
 	"internal/fmtsort"
 	"math"
 	"reflect"
+	"sort"
 	"strings"
 	"testing"
 	"unsafe"
@@ -188,9 +189,19 @@ func sprintKey(key reflect.Value) string {
 
 var (
 	ints  [3]int
-	chans = [3]chan int{make(chan int), make(chan int), make(chan int)}
+	chans = makeChans()
 )
 
+func makeChans() []chan int {
+	cs := []chan int{make(chan int), make(chan int), make(chan int)}
+	// Order channels by address. See issue #49431.
+	// TODO: pin these pointers once pinning is available (#46787).
+	sort.Slice(cs, func(i, j int) bool {
+		return uintptr(reflect.ValueOf(cs[i]).UnsafePointer()) < uintptr(reflect.ValueOf(cs[j]).UnsafePointer())
+	})
+	return cs
+}
+
 func pointerMap() map[*int]string {
 	m := make(map[*int]string)
 	for i := 2; i >= 0; i-- {