compiler: More cases that need a temporary for interface conversion.

From-SVN: r218952

gcc/go/gofrontend/expressions.cc

@@ -5142,6 +5142,9 @@ Expression*
 Binary_expression::do_flatten(Gogo* gogo, Named_object*,
                               Statement_inserter* inserter)
 {
+  if (this->classification() == EXPRESSION_ERROR)
+    return this;
+
   Location loc = this->location();
   Temporary_statement* temp;
   if (this->left_->type()->is_string_type()
@@ -6876,11 +6879,17 @@ Builtin_call_expression::do_lower(Gogo* gogo, Named_object* function,
 Expression*
 Builtin_call_expression::do_flatten(Gogo*, Named_object*,
                                     Statement_inserter* inserter)
-{
-  if (this->code_ == BUILTIN_APPEND
-      || this->code_ == BUILTIN_COPY)
 {
   Location loc = this->location();
+
+  switch (this->code_)
+    {
+    default:
+      break;
+
+    case BUILTIN_APPEND:
+    case BUILTIN_COPY:
+      {
 	Type* at = this->args()->front()->type();
 	for (Expression_list::iterator pa = this->args()->begin();
 	     pa != this->args()->end();
@@ -6901,6 +6910,23 @@ Builtin_call_expression::do_flatten(Gogo*, Named_object*,
 	      }
 	  }
       }
+      break;
+
+    case BUILTIN_PANIC:
+      for (Expression_list::iterator pa = this->args()->begin();
+	   pa != this->args()->end();
+	   ++pa)
+	{
+	  if (!(*pa)->is_variable() && (*pa)->type()->interface_type() != NULL)
+	    {
+	      Temporary_statement* temp =
+		Statement::make_temporary(NULL, *pa, loc);
+	      inserter->insert(temp);
+	      *pa = Expression::make_temporary_reference(temp, loc);
+	    }
+	}
+    }
+
   return this;
 }
 

gcc/go/gofrontend/statements.cc

@@ -421,6 +421,28 @@ Temporary_statement::do_check_types(Gogo*)
     }
 }
 
+// Flatten a temporary statement: add another temporary when it might
+// be needed for interface conversion.
+
+Statement*
+Temporary_statement::do_flatten(Gogo*, Named_object*, Block*,
+				Statement_inserter* inserter)
+{
+  if (this->type_ != NULL
+      && this->init_ != NULL
+      && !Type::are_identical(this->type_, this->init_->type(), false, NULL)
+      && this->init_->type()->interface_type() != NULL
+      && !this->init_->is_variable())
+    {
+      Temporary_statement *temp =
+	Statement::make_temporary(NULL, this->init_, this->location());
+      inserter->insert(temp);
+      this->init_ = Expression::make_temporary_reference(temp,
+							 this->location());
+    }
+  return this;
+}
+
 // Convert to backend representation.
 
 Bstatement*
@@ -440,9 +462,10 @@ Temporary_statement::do_get_backend(Translate_context* context)
     binit = this->init_->get_backend(context);
   else
     {
-      Expression* init = Expression::make_cast(this->type_, this->init_,
+      Expression* init = Expression::convert_for_assignment(context->gogo(),
+							    this->type_,
+							    this->init_,
 							    this->location());
-      context->gogo()->lower_expression(context->function(), NULL, &init);
       binit = init->get_backend(context);
     }
 

gcc/go/gofrontend/statements.h

@@ -550,6 +550,9 @@ class Temporary_statement : public Statement
   void
   do_check_types(Gogo*);
 
+  Statement*
+  do_flatten(Gogo*, Named_object*, Block*, Statement_inserter*);
+
   Bstatement*
   do_get_backend(Translate_context*);