gc: minor changes for inlining

Copied from 5400043 since they stand alone from inlining.

R=lvd
CC=golang-dev
https://golang.org/cl/5479046

src/cmd/gc/dcl.c

@@ -642,7 +642,7 @@ funcargs2(Type *t)
 		for(ft=getthisx(t)->type; ft; ft=ft->down) {
 			if(!ft->nname || !ft->nname->sym)
 				continue;
-			n = newname(ft->nname->sym);
+			n = ft->nname;  // no need for newname(ft->nname->sym)
 			n->type = ft->type;
 			declare(n, PPARAM);
 		}
@@ -651,7 +651,7 @@ funcargs2(Type *t)
 		for(ft=getinargx(t)->type; ft; ft=ft->down) {
 			if(!ft->nname || !ft->nname->sym)
 				continue;
-			n = newname(ft->nname->sym);
+			n = ft->nname;
 			n->type = ft->type;
 			declare(n, PPARAM);
 		}
@@ -660,7 +660,7 @@ funcargs2(Type *t)
 		for(ft=getoutargx(t)->type; ft; ft=ft->down) {
 			if(!ft->nname || !ft->nname->sym)
 				continue;
-			n = newname(ft->nname->sym);
+			n = ft->nname;
 			n->type = ft->type;
 			declare(n, PPARAMOUT);
 		}
@@ -845,6 +845,7 @@ tofunargs(NodeList *l)
 	for(tp = &t->type; l; l=l->next) {
 		f = structfield(l->n);
 		f->funarg = 1;
+
 		// esc.c needs to find f given a PPARAM to add the tag.
 		if(l->n->left && l->n->left->class == PPARAM)
 			l->n->left->paramfld = f;
@@ -1224,6 +1225,7 @@ methodname1(Node *n, Node *t)
 	}
 	if(t->sym == S || isblank(n))
 		return newname(n->sym);
+
 	if(star)
 		p = smprint("(%s%S).%S", star, t->sym, n->sym);
 	else

src/cmd/gc/typecheck.c

@@ -1685,6 +1685,7 @@ lookdot(Node *n, Type *t, int dostrcmp)
 		n->right = methodname(n->right, n->left->type);
 		n->xoffset = f2->width;
 		n->type = f2->type;
+//		print("lookdot found [%p] %T\n", f2->type, f2->type);
 		n->op = ODOTMETH;
 		return 1;
 	}
@@ -2441,7 +2442,7 @@ typecheckfunc(Node *n)
 	if((t = n->nname->type) == T)
 		return;
 	n->type = t;
-
+	t->nname = n->nname;
 	rcvr = getthisx(t)->type;
 	if(rcvr != nil && n->shortname != N && !isblank(n->shortname))
 		addmethod(n->shortname->sym, t, 1);

src/cmd/gc/walk.c

@@ -167,6 +167,8 @@ walkstmt(Node **np)
 
 	setlineno(n);
 
+	walkstmtlist(n->ninit);
+
 	switch(n->op) {
 	default:
 		if(n->op == ONAME)
@@ -243,7 +245,6 @@ walkstmt(Node **np)
 		break;
 
 	case OFOR:
-		walkstmtlist(n->ninit);
 		if(n->ntest != N) {
 			walkstmtlist(n->ntest->ninit);
 			init = n->ntest->ninit;
@@ -256,7 +257,6 @@ walkstmt(Node **np)
 		break;
 
 	case OIF:
-		walkstmtlist(n->ninit);
 		walkexpr(&n->ntest, &n->ninit);
 		walkstmtlist(n->nbody);
 		walkstmtlist(n->nelse);
@@ -384,6 +384,12 @@ walkexpr(Node **np, NodeList **init)
 		fatal("walkexpr init == &n->ninit");
 	}
 
+	if(n->ninit != nil) {
+		walkstmtlist(n->ninit);
+		*init = concat(*init, n->ninit);
+		n->ninit = nil;
+	}
+
 	// annoying case - not typechecked
 	if(n->op == OKEY) {
 		walkexpr(&n->left, init);
@@ -1229,7 +1235,7 @@ ascompatee(int op, NodeList *nl, NodeList *nr, NodeList **init)
 
 	// cannot happen: caller checked that lists had same length
 	if(ll || lr)
-		yyerror("error in shape across %O", op);
+		yyerror("error in shape across %+H %O %+H", nl, op, nr);
 	return nn;
 }
 

src/pkg/exp/types/gcimporter.go

@@ -145,18 +145,14 @@ func GcImporter(imports map[string]*ast.Object, path string) (pkg *ast.Object, e
 
 // Declare inserts a named object of the given kind in scope.
 func (p *gcParser) declare(scope *ast.Scope, kind ast.ObjKind, name string) *ast.Object {
-	// a type may have been declared before - if it exists
-	// already in the respective package scope, return that
-	// type
-	if kind == ast.Typ {
-		if obj := scope.Lookup(name); obj != nil {
-			assert(obj.Kind == ast.Typ)
-			return obj
-		}
+	// the object may have been imported before - if it exists
+	// already in the respective package scope, return that object
+	if obj := scope.Lookup(name); obj != nil {
+		assert(obj.Kind == kind)
+		return obj
 	}
 
-	// any other object must be a newly declared object -
-	// create it and insert it into the package scope
+	// otherwise create a new object and insert it into the package scope
 	obj := ast.NewObj(kind, name)
 	if scope.Insert(obj) != nil {
 		p.errorf("already declared: %v %s", kind, obj.Name)