implement new restrictions on what
can be compared/hashed.

R=r
DELTA=351  (201 added, 80 deleted, 70 changed)
OCL=23423
CL=23481
diff --git a/test/cmp5.go b/test/cmp5.go
new file mode 100644
index 0000000..7500974
--- /dev/null
+++ b/test/cmp5.go
@@ -0,0 +1,15 @@
+// $G $D/$F.go && $L $F.$A && ! ./$A.out
+
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+func main()
+{
+	var b map[string]int;
+	var ib interface{} = b;
+	var m = make(map[interface{}] int);
+	m[ib] = 1;
+}