diff --git a/go/types/api.go b/go/types/api.go
index 6c8f7648..c49a79c7 100644
--- a/go/types/api.go
+++ b/go/types/api.go
@@ -89,29 +89,28 @@ type Config struct {
 	Sizeof func(Type) int64
 }
 
-// Info holds result type information for a package.
+// Info holds result type information for a type-checked package.
+// Only the information for which a map is provided is collected.
+// If the package has type errors, the collected information may
+// be incomplete.
 type Info struct {
-	// If Types != nil, it records the expression and corresponding type
-	// for each expression that is type-checked. Identifiers declaring a
-	// variable are recorded in Objects, not Types.
+	// Types maps expressions to their types. Identifiers on the
+	// lhs of declarations are collected in Objects, not Types.
 	Types map[ast.Expr]Type
 
-	// If Values != nil, it records the expression and corresponding value
-	// for each constant expression that is type-checked.
+	// Values maps constant expressions to their values.
 	Values map[ast.Expr]exact.Value
 
-	// If Objects != nil, it records the identifier and corresponding object
-	// for each identifier that is type-checked (including package names,
-	// dots "." of dot-imports, and blank "_" identifiers). For identifiers
-	// that are not declared (due to an error, or because they are symbolic
-	// as the t in t := x.(type) of a type switch header), the corresponding
-	// object is nil.
+	// Objects maps identifiers to their corresponding objects (including
+	// package names, dots "." of dot-imports, and blank "_" identifiers).
+	// For identifiers that do not denote objects (e.g., blank identifiers
+	// on the lhs of assignments, or symbolic variables t in t := x.(type)
+	// of type switch headers), the corresponding objects are nil.
 	// BUG(gri) Label identifiers in break, continue, or goto statements
-	// are not recorded.
+	// are not yet mapped.
 	Objects map[*ast.Ident]Object
 
-	// If Implicits != nil, it records the node and corresponding object for
-	// each node that is type-checked and that implicitly declared an object.
+	// Implicits maps nodes to their implicitly declared objects, if any.
 	// The following node and object types may appear:
 	//
 	//	node               declared object
@@ -122,10 +121,7 @@ type Info struct {
 	//
 	Implicits map[ast.Node]Object
 
-	// If Selections != nil, it records the selector expression and corresponding
-	// selection, i.e., package object (qualified identifier), struct field (field
-	// selector), or method (method expression or value) for each selector expression
-	// that is type-checked.
+	// Selections maps selector expressions to their corresponding selections.
 	Selections map[*ast.SelectorExpr]*Selection
 }
 
diff --git a/go/types/assignments.go b/go/types/assignments.go
index d7912539..569d46fe 100644
--- a/go/types/assignments.go
+++ b/go/types/assignments.go
@@ -306,7 +306,9 @@ func (check *checker) shortVarDecl(lhs, rhs []ast.Expr) {
 				// declare new variable
 				obj = NewVar(ident.Pos(), check.pkg, ident.Name, nil)
 			}
-			check.recordObject(ident, obj) // obj may be nil
+			if obj != nil {
+				check.recordObject(ident, obj)
+			}
 		} else {
 			check.errorf(lhs.Pos(), "cannot declare %s", lhs)
 		}
diff --git a/go/types/call.go b/go/types/call.go
index 6b914699..d98964fe 100644
--- a/go/types/call.go
+++ b/go/types/call.go
@@ -169,7 +169,7 @@ func (check *checker) selector(x *operand, e *ast.SelectorExpr) {
 	// can only appear in qualified identifiers which are mapped to
 	// selector expressions.
 	if ident, ok := e.X.(*ast.Ident); ok {
-		if pkg, ok := check.topScope.LookupParent(ident.Name).(*Package); ok {
+		if pkg, _ := check.topScope.LookupParent(ident.Name).(*Package); pkg != nil {
 			check.recordObject(ident, pkg)
 			exp := pkg.scope.Lookup(sel)
 			if exp == nil {
diff --git a/go/types/gcimporter.go b/go/types/gcimporter.go
index f4b70d0a..fa76d46f 100644
--- a/go/types/gcimporter.go
+++ b/go/types/gcimporter.go
@@ -107,7 +107,6 @@ func GcImportData(imports map[string]*Package, filename, id string, data *bufio.
 // corresponding package object to the imports map, and returns the object.
 // Local import paths are interpreted relative to the current working directory.
 // The imports map must contains all packages already imported.
-// GcImport satisfies the ast.Importer signature.
 //
 func GcImport(imports map[string]*Package, path string) (pkg *Package, err error) {
 	if path == "unsafe" {
diff --git a/go/types/lookup.go b/go/types/lookup.go
index d7ebd38b..048ac477 100644
--- a/go/types/lookup.go
+++ b/go/types/lookup.go
@@ -236,7 +236,7 @@ func MissingMethod(typ Type, T *Interface, static bool) (method *Func, wrongType
 		return
 	}
 
-	// TODO(gri) Consider using methods sets here. Might be more efficient.
+	// TODO(gri) Consider using method sets here. Might be more efficient.
 
 	if ityp, _ := typ.Underlying().(*Interface); ityp != nil {
 		for _, m := range T.methods {
diff --git a/go/types/resolver.go b/go/types/resolver.go
index 290d7cbc..7846694e 100644
--- a/go/types/resolver.go
+++ b/go/types/resolver.go
@@ -27,7 +27,7 @@ func (check *checker) declareObj(scope *Scope, id *ast.Ident, obj Object) {
 	if alt := scope.Insert(obj); alt != nil {
 		check.errorf(obj.Pos(), "%s redeclared in this block", obj.Name())
 		check.reportAltDecl(alt)
-		obj = nil
+		return
 	}
 	if id != nil {
 		check.recordObject(id, obj)
@@ -38,7 +38,7 @@ func (check *checker) declareFld(oset *objset, id *ast.Ident, obj Object) {
 	if alt := oset.insert(obj); alt != nil {
 		check.errorf(obj.Pos(), "%s redeclared", obj.Name())
 		check.reportAltDecl(alt)
-		obj = nil
+		return
 	}
 	if id != nil {
 		check.recordObject(id, obj)
@@ -131,7 +131,6 @@ func (check *checker) resolveFiles(files []*ast.File) {
 		// spec: "A package-scope or file-scope identifier with name init
 		// may only be declared to be a function with this (func()) signature."
 		if ident.Name == "init" {
-			check.recordObject(ident, nil)
 			check.errorf(ident.Pos(), "cannot declare init - must be func")
 			return
 		}
@@ -529,8 +528,6 @@ func (check *checker) typeDecl(obj *TypeName, typ ast.Expr, def *Named, cycleOk
 
 	// check each method
 	for _, m := range methods {
-		ident := check.objMap[m].fdecl.Name
-
 		if alt := mset.insert(m); alt != nil {
 			switch alt.(type) {
 			case *Var:
@@ -541,19 +538,14 @@ func (check *checker) typeDecl(obj *TypeName, typ ast.Expr, def *Named, cycleOk
 				unreachable()
 			}
 			check.reportAltDecl(alt)
-			m = nil
+			continue
 		}
-
-		// If the method is valid, type-check its signature,
-		// and collect it with the named base type.
-		if m != nil {
-			check.recordObject(ident, m)
-			check.objDecl(m, nil, true)
-			// Methods with blank _ names cannot be found.
-			// Don't add them to the method list.
-			if m.name != "_" {
-				named.methods = append(named.methods, m)
-			}
+		check.recordObject(check.objMap[m].fdecl.Name, m)
+		check.objDecl(m, nil, true)
+		// Methods with blank _ names cannot be found.
+		// Don't add them to the method list.
+		if m.name != "_" {
+			named.methods = append(named.methods, m)
 		}
 	}
 
diff --git a/go/types/typexpr.go b/go/types/typexpr.go
index cc480668..cde211d4 100644
--- a/go/types/typexpr.go
+++ b/go/types/typexpr.go
@@ -23,7 +23,6 @@ func (check *checker) ident(x *operand, e *ast.Ident, def *Named, cycleOk bool)
 	x.expr = e
 
 	obj := check.topScope.LookupParent(e.Name)
-	check.recordObject(e, obj)
 	if obj == nil {
 		if e.Name == "_" {
 			check.errorf(e.Pos(), "cannot use _ as value or type")
@@ -32,6 +31,7 @@ func (check *checker) ident(x *operand, e *ast.Ident, def *Named, cycleOk bool)
 		}
 		return
 	}
+	check.recordObject(e, obj)
 
 	typ := obj.Type()
 	if typ == nil {