go/ssa/interp: fix failing recover2.go test

The "unhashable" panic message had changed in go1.14.

Fixes golang/go#34089

Change-Id: I6ba97d33fefee9e217b65904db2b07c2091d80be
Reviewed-on: https://go-review.googlesource.com/c/tools/+/621676
LUCI-TryBot-Result: Go LUCI <[email protected]>
Auto-Submit: Alan Donovan <[email protected]>
Reviewed-by: Tim King <[email protected]>
Commit-Queue: Alan Donovan <[email protected]>

Author: adonovan

go/ssa/interp/interp_test.go

@@ -153,12 +153,6 @@ func init() {
 }
 
 func run(t *testing.T, input string, goroot string) {
-	// The recover2 test case is broken on Go 1.14+. See golang/go#34089.
-	// TODO(matloob): Fix this.
-	if filepath.Base(input) == "recover2.go" {
-		t.Skip("The recover2.go test is broken in go1.14+. See golang.org/issue/34089.")
-	}
-
 	t.Logf("Input: %s\n", input)
 
 	start := time.Now()

go/ssa/interp/value.go

@@ -141,7 +141,7 @@ func (x array) hash(t types.Type) int {
 	h := 0
 	tElt := t.Underlying().(*types.Array).Elem()
 	for _, xi := range x {
-		h += hash(tElt, xi)
+		h += hash(t, tElt, xi)
 	}
 	return h
 }
@@ -164,7 +164,7 @@ func (x structure) hash(t types.Type) int {
 	h := 0
 	for i, n := 0, tStruct.NumFields(); i < n; i++ {
 		if f := tStruct.Field(i); !f.Anonymous() {
-			h += hash(f.Type(), x[i])
+			h += hash(t, f.Type(), x[i])
 		}
 	}
 	return h
@@ -183,8 +183,8 @@ func (x iface) eq(t types.Type, _y interface{}) bool {
 	return sameType(x.t, y.t) && (x.t == nil || equals(x.t, x.v, y.v))
 }
 
-func (x iface) hash(_ types.Type) int {
-	return hashType(x.t)*8581 + hash(x.t, x.v)
+func (x iface) hash(outer types.Type) int {
+	return hashType(x.t)*8581 + hash(outer, x.t, x.v)
 }
 
 func (x rtype) hash(_ types.Type) int {
@@ -256,7 +256,8 @@ func equals(t types.Type, x, y value) bool {
 }
 
 // Returns an integer hash of x such that equals(x, y) => hash(x) == hash(y).
-func hash(t types.Type, x value) int {
+// The outer type is used only for the "unhashable" panic message.
+func hash(outer, t types.Type, x value) int {
 	switch x := x.(type) {
 	case bool:
 		if x {
@@ -308,7 +309,7 @@ func hash(t types.Type, x value) int {
 	case rtype:
 		return x.hash(t)
 	}
-	panic(fmt.Sprintf("%T is unhashable", x))
+	panic(fmt.Sprintf("unhashable type %v", outer))
 }
 
 // reflect.Value struct values don't have a fixed shape, since the