compiler: avoid orphaning Bexpressions when processing conversions
The method Type_conversion_expression::do_get_backend was (in some
circumstances) creating a Bexpression for the source expression of the
conversion and then throwing it away before using it. Fix up this
method to insure that the call to get_backend() on the source
expression is only made when the result will be used.
Change-Id: I8424ed358a0455e72aa25ee9c3642c70404db9f5
Reviewed-on: https://go-review.googlesource.com/45350
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
diff --git a/go/expressions.cc b/go/expressions.cc
index d6d27ee..5eec731 100644
--- a/go/expressions.cc
+++ b/go/expressions.cc
@@ -3410,11 +3410,13 @@
Gogo* gogo = context->gogo();
Btype* btype = type->get_backend(gogo);
- Bexpression* bexpr = this->expr_->get_backend(context);
Location loc = this->location();
if (Type::are_identical(type, expr_type, false, NULL))
- return gogo->backend()->convert_expression(btype, bexpr, loc);
+ {
+ Bexpression* bexpr = this->expr_->get_backend(context);
+ return gogo->backend()->convert_expression(btype, bexpr, loc);
+ }
else if (type->interface_type() != NULL
|| expr_type->interface_type() != NULL)
{
@@ -3483,6 +3485,7 @@
else if (type->is_numeric_type())
{
go_assert(Type::are_convertible(type, expr_type, NULL));
+ Bexpression* bexpr = this->expr_->get_backend(context);
return gogo->backend()->convert_expression(btype, bexpr, loc);
}
else if ((type->is_unsafe_pointer_type()
@@ -3493,7 +3496,10 @@
|| (this->may_convert_function_types_
&& type->function_type() != NULL
&& expr_type->function_type() != NULL))
- return gogo->backend()->convert_expression(btype, bexpr, loc);
+ {
+ Bexpression* bexpr = this->expr_->get_backend(context);
+ return gogo->backend()->convert_expression(btype, bexpr, loc);
+ }
else
{
Expression* conversion =