undo CL 12787044 / ed695cdf962b

The NetBSD and OpenBSD failures are apparently real,
not due to the test bug fixed in 100b9fc0c46f.

««« original CL description
runtime/pprof: test netbsd and openbsd again

Maybe these will work now.

R=golang-dev, dvyukov, bradfitz
CC=golang-dev
https://golang.org/cl/12787044
»»»

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/12873043

src/pkg/runtime/pprof/pprof.go

@@ -20,7 +20,7 @@ import (
 	"text/tabwriter"
 )
 
-// BUG(rsc): Profiles are incomplete and inaccuate on OS X.
+// BUG(rsc): Profiles are incomplete and inaccuate on NetBSD, OpenBSD, and OS X.
 // See http://golang.org/issue/6047 for details.
 
 // A Profile is a collection of stack traces showing the call sequences

src/pkg/runtime/pprof/pprof_test.go

@@ -175,9 +175,9 @@ func TestCPUProfileWithFork(t *testing.T) {
 
 // Operating systems that are expected to fail the tests. See issue 6047.
 var badOS = map[string]bool{
-	"darwin": true,
-	//"netbsd":  true,
-	//"openbsd": true,
+	"darwin":  true,
+	"netbsd":  true,
+	"openbsd": true,
 }
 
 func TestBlockProfile(t *testing.T) {