compiler: Fix parameter references in method expressions.

From-SVN: r183825

gcc/go/gofrontend/expressions.cc

@@ -11711,10 +11711,21 @@ Selector_expression::lower_method_expression(Gogo* gogo)
   const Typed_identifier_list* method_parameters = method_type->parameters();
   if (method_parameters != NULL)
     {
+      int i = 0;
       for (Typed_identifier_list::const_iterator p = method_parameters->begin();
 	   p != method_parameters->end();
-	   ++p)
-	parameters->push_back(*p);
+	   ++p, ++i)
+	{
+	  if (!p->name().empty() && p->name() != Import::import_marker)
+	    parameters->push_back(*p);
+	  else
+	    {
+	      char buf[20];
+	      snprintf(buf, sizeof buf, "$param%d", i);
+	      parameters->push_back(Typed_identifier(buf, p->type(),
+						     p->location()));
+	    }
+	}
     }
 
   const Typed_identifier_list* method_results = method_type->results();
@@ -11774,14 +11785,14 @@ Selector_expression::lower_method_expression(Gogo* gogo)
     }
 
   Expression_list* args;
-  if (method_parameters == NULL)
+  if (parameters->size() <= 1)
     args = NULL;
   else
     {
       args = new Expression_list();
-      for (Typed_identifier_list::const_iterator p = method_parameters->begin();
-	   p != method_parameters->end();
-	   ++p)
+      Typed_identifier_list::const_iterator p = parameters->begin();
+      ++p;
+      for (; p != parameters->end(); ++p)
 	{
 	  vno = gogo->lookup(p->name(), NULL);
 	  go_assert(vno != NULL);