diff --git a/src/runtime/runtime_test.go b/src/runtime/runtime_test.go
index 0f2998b35b..6c628f8903 100644
--- a/src/runtime/runtime_test.go
+++ b/src/runtime/runtime_test.go
@@ -7,7 +7,10 @@ package runtime_test
 import (
 	"flag"
 	"fmt"
+	"internal/asan"
 	"internal/cpu"
+	"internal/msan"
+	"internal/race"
 	"internal/runtime/atomic"
 	"internal/testenv"
 	"io"
@@ -329,6 +332,9 @@ func TestAppendGrowthHeap(t *testing.T) {
 }
 
 func TestAppendGrowthStack(t *testing.T) {
+	if race.Enabled || asan.Enabled || msan.Enabled {
+		t.Skip("instrumentation breaks this optimization")
+	}
 	var x []int64
 	check := func(want int) {
 		if cap(x) != want {
@@ -338,7 +344,7 @@ func TestAppendGrowthStack(t *testing.T) {
 
 	check(0)
 	want := 32 / 8 // 32 is the default for cmd/compile/internal/base.DebugFlags.VariableMakeThreshold
-	if Raceenabled || testenv.OptimizationOff() {
+	if testenv.OptimizationOff() {
 		want = 1
 	}
 	for i := 1; i <= 100; i++ {