embedded types

auto & on methods

R=r
OCL=17682
CL=17682

src/cmd/gc/go.h

@@ -584,6 +584,8 @@ int	isinter(Type*);
 int	isnilinter(Type*);
 Sym*	globalsig(Type*);
 Type*	ismethod(Type*);
+Type*	methtype(Type*);
+int	needaddr(Type*);
 Sym*	signame(Type*, int);
 int	bytearraysz(Type*);
 int	eqtype(Type*, Type*, int);

src/cmd/gc/subr.c

@@ -1518,6 +1518,51 @@ out:
 	return t;
 }
 
+/*
+ * this is ismethod() without side effects
+ */
+Type*
+methtype(Type *t)
+{
+	Sym *s;
+
+	if(t == T)
+		return T;
+	if(t->etype == TINTER || (t->etype == tptr && t->type->etype == TINTER))
+		return T;
+	s = t->sym;
+	if(s != S)
+		return t;
+	if(!isptr[t->etype])
+		return T;
+	t = t->type;
+	if(t == T)
+		return T;
+	s = t->sym;
+	if(s != S)
+		return t;
+	return T;
+}
+
+/*
+ * this is another ismethod()
+ * returns 1 if t=T and method wants *T
+ */
+int
+needaddr(Type *t)
+{
+	Sym *s;
+
+	if(t == T)
+		return 0;
+	if(t->etype == TINTER || (t->etype == tptr && t->type->etype == TINTER))
+		return 0;
+	s = t->sym;
+	if(s != S && t->methptr == 2)
+		return 1;
+	return 0;
+}
+
 int
 iscomposite(Type *t)
 {

src/cmd/gc/walk.c

@@ -1422,30 +1422,6 @@ walkselect(Node *sel)
 	lineno = lno;
 }
 
-Type*
-methtype(Type *t)
-{
-	Sym *s;
-
-	// this is ismethod() without diagnostics
-	if(t == T)
-		return T;
-	if(t->etype == TINTER || (t->etype == tptr && t->type->etype == TINTER))
-		return T;
-	s = t->sym;
-	if(s != S && s->name[0] != '_')
-		return t;
-	if(!isptr[t->etype])
-		return T;
-	t = t->type;
-	if(t == T)
-		return T;
-	s = t->sym;
-	if(s != S && s->name[0] != '_')
-		return t;
-	return T;
-}
-
 Type*
 lookdot1(Node *n, Type *f)
 {
@@ -1495,6 +1471,10 @@ lookdot(Node *n, Type *t)
 	}
 
 	if(f2 != T) {
+		if(needaddr(n->left->type)) {
+			n->left = nod(OADDR, n->left, N);
+			n->left->type = ptrto(n->left->left->type);
+		}
 		n->right = methodname(n->right, ismethod(n->left->type));
 		n->xoffset = f2->width;
 		n->type = f2->type;