diff --git a/share/shutter/resources/modules/Shutter/Draw/DrawingTool.pm b/share/shutter/resources/modules/Shutter/Draw/DrawingTool.pm
index fef409c3..490bb2ec 100644
--- a/share/shutter/resources/modules/Shutter/Draw/DrawingTool.pm
+++ b/share/shutter/resources/modules/Shutter/Draw/DrawingTool.pm
@@ -675,16 +675,16 @@ sub setup_right_vbox_c {
 	#get current pixbuf
 	my $pixbuf = $self->{_view}->get_pixbuf || $self->{_drawing_pixbuf};
 
-	sub value_callback {
+	my $value_callback = sub {
 		$self->{_selector}->set_selection({x=>$self->{_x_spin_w}->get_value, y=>$self->{_y_spin_w}->get_value, width=>$self->{_width_spin_w}->get_value, height=>$self->{_height_spin_w}->get_value});
-	}
+	};
 
 	#X
 	my $xw_label = Gtk3::Label->new($self->{_d}->get("X") . ":");
 	$self->{_x_spin_w} = Gtk3::SpinButton->new_with_range(0, $pixbuf->get_width, 1);
 	$self->{_x_spin_w}->set_value(0);
 	$self->{_x_spin_w_handler} = $self->{_x_spin_w}->signal_connect(
-		'value-changed' => \&value_callback);
+		'value-changed' => $value_callback);
 
 	my $xw_hbox = Gtk3::HBox->new(FALSE, 5);
 	$xw_hbox->pack_start($xw_label,          FALSE, FALSE, 5);
@@ -695,7 +695,7 @@ sub setup_right_vbox_c {
 	$self->{_y_spin_w} = Gtk3::SpinButton->new_with_range(0, $pixbuf->get_height, 1);
 	$self->{_y_spin_w}->set_value(0);
 	$self->{_y_spin_w_handler} = $self->{_y_spin_w}->signal_connect(
-		'value-changed' => \&value_callback);
+		'value-changed' => $value_callback);
 
 	my $yw_hbox = Gtk3::HBox->new(FALSE, 5);
 	$yw_hbox->pack_start($yw_label,          FALSE, FALSE, 5);
@@ -706,7 +706,7 @@ sub setup_right_vbox_c {
 	$self->{_width_spin_w} = Gtk3::SpinButton->new_with_range(0, $pixbuf->get_width, 1);
 	$self->{_width_spin_w}->set_value(0);
 	$self->{_width_spin_w_handler} = $self->{_width_spin_w}->signal_connect(
-		'value-changed' => \&value_callback);
+		'value-changed' => $value_callback);
 
 	my $ww_hbox = Gtk3::HBox->new(FALSE, 5);
 	$ww_hbox->pack_start($widthw_label,          FALSE, FALSE, 5);
@@ -717,7 +717,7 @@ sub setup_right_vbox_c {
 	$self->{_height_spin_w} = Gtk3::SpinButton->new_with_range(0, $pixbuf->get_height, 1);
 	$self->{_height_spin_w}->set_value(0);
 	$self->{_height_spin_w_handler} = $self->{_height_spin_w}->signal_connect(
-		'value-changed' => \&value_callback);
+		'value-changed' => $value_callback);
 
 	my $hw_hbox = Gtk3::HBox->new(FALSE, 5);
 	$hw_hbox->pack_start($heightw_label,          FALSE, FALSE, 5);