Associate the correct type to method receivers (instead of Dynamic type).

runtime/vm/flow_graph_builder.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/flow_graph_builder.h"
 
 #include "vm/ast_printer.h"
 #include "vm/bit_vector.h"
 #include "vm/code_descriptors.h"
 #include "vm/dart_entry.h"
@@ skipping 329 matching lines @@
 
   for (intptr_t i = 0; i < node->inlined_finally_list_length(); i++) {
     EffectGraphVisitor for_effect(owner(), temp_index());
     node->InlinedFinallyNodeAt(i)->Visit(&for_effect);
     Append(for_effect);
     if (!is_open()) return;
   }
 
   Value* return_value = for_value.value();
   if (FLAG_enable_type_checks) {
-    const RawFunction::Kind kind = owner()->parsed_function().function().kind();
-    const bool is_implicit_getter =
-        (kind == RawFunction::kImplicitGetter) ||
-        (kind == RawFunction::kConstImplicitGetter);
-    const bool is_static = owner()->parsed_function().function().is_static();
+    const Function& function = owner()->parsed_function().function();
+    const bool is_implicit_dynamic_getter =
+        (!function.is_static() &&
+        ((function.kind() == RawFunction::kImplicitGetter) ||
+         (function.kind() == RawFunction::kConstImplicitGetter)));
     // Implicit getters do not need a type check at return, unless they compute
     // the initial value of a static field.
-    if (is_static || !is_implicit_getter) {
+    // The body of a constructor cannot modify the type of the
+    // constructed instance, which is passed in as an implicit parameter.
+    // However, factories may create an instance of the wrong type.
+    if (!is_implicit_dynamic_getter && !function.IsConstructor()) {
       const AbstractType& dst_type =
           AbstractType::ZoneHandle(
               owner()->parsed_function().function().result_type());
       const String& dst_name =
           String::ZoneHandle(Symbols::New("function result"));
       return_value = BuildAssignableValue(node->value()->token_pos(),
                                           return_value,
                                           dst_type,
                                           dst_name);
     }
@@ skipping 2317 matching lines @@
   char* chars = reinterpret_cast<char*>(
       Isolate::Current()->current_zone()->Allocate(len));
   OS::SNPrint(chars, len, kFormat, function_name, reason);
   const Error& error = Error::Handle(
       LanguageError::New(String::Handle(String::New(chars))));
   Isolate::Current()->long_jump_base()->Jump(1, error);
 }
 
 
 }  // namespace dart