cmd/internal/ld: make a few more symbols local

The symbols for the actual data in a constant string or bytes literal should
be local.

Change-Id: Idafcfba9a638eaa4e460e5103d96843960559b35
Reviewed-on: https://go-review.googlesource.com/8772Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>

src/cmd/internal/ld/symtab.go

@@ -367,9 +367,18 @@ func symtab() {
 	// just defined above will be first.
 	// hide the specific symbols.
 	for s := Ctxt.Allsym; s != nil; s = s.Allsym {
-		if !s.Reachable || s.Special != 0 || s.Type != SRODATA {
+		if !s.Reachable || s.Special != 0 {
 			continue
 		}
+
+		if strings.Contains(s.Name, "..gostring.") || strings.Contains(s.Name, "..gobytes.") {
+			s.Local = true
+		}
+
+		if s.Type != SRODATA {
+			continue
+		}
+
 		if strings.HasPrefix(s.Name, "type.") && !DynlinkingGo() {
 			s.Type = STYPE
 			s.Hide = 1