diff --git a/src/cmd/dist/build.go b/src/cmd/dist/build.go
index 212dd172a3..54e3fdf040 100644
--- a/src/cmd/dist/build.go
+++ b/src/cmd/dist/build.go
@@ -620,7 +620,7 @@ func install(dir string) {
 	}
 
 	// For package runtime, copy some files into the work space.
-	if dir == "runtime" {
+	if dir == "runtime" || strings.HasPrefix(dir, "runtime/internal/") {
 		xmkdirall(pathf("%s/pkg/include", goroot))
 		// For use by assembly and C files.
 		copyfile(pathf("%s/pkg/include/textflag.h", goroot),