diff --git a/lib/Slic3r/ExtrusionLoop.pm b/lib/Slic3r/ExtrusionLoop.pm
index c97684f0..1cdc27b9 100644
--- a/lib/Slic3r/ExtrusionLoop.pm
+++ b/lib/Slic3r/ExtrusionLoop.pm
@@ -33,11 +33,6 @@ sub pack {
     return $o;
 }
 
-sub shortest_path {
-    my $self = shift;
-    return $self;
-}
-
 sub split_at_index {
     my $self = shift;
     my ($index) = @_;
diff --git a/lib/Slic3r/ExtrusionPath.pm b/lib/Slic3r/ExtrusionPath.pm
index 717e1ad6..63f2267e 100644
--- a/lib/Slic3r/ExtrusionPath.pm
+++ b/lib/Slic3r/ExtrusionPath.pm
@@ -58,11 +58,6 @@ sub pack {
 # no-op, this allows to use both packed and non-packed objects in Collections
 sub unpack { $_[0] }
 
-sub shortest_path {
-    my $self = shift;
-    return $self;
-}
-
 sub clip_end {
     my $self = shift;
     my ($distance) = @_;
diff --git a/lib/Slic3r/Layer.pm b/lib/Slic3r/Layer.pm
index a95570d6..43f2b264 100644
--- a/lib/Slic3r/Layer.pm
+++ b/lib/Slic3r/Layer.pm
@@ -349,13 +349,14 @@ sub make_perimeters {
     # add thin walls as perimeters
     {
         my @thin_paths = ();
+        my %properties = (
+            role            => EXTR_ROLE_PERIMETER,
+            flow_spacing    => $self->perimeters_flow->spacing,
+        );
         for (@{ $self->thin_walls }) {
-            if ($_->isa('Slic3r::Polygon')) {
-                push @thin_paths, Slic3r::ExtrusionLoop->pack(polygon => $_, role => EXTR_ROLE_PERIMETER);
-            } else {
-                push @thin_paths, Slic3r::ExtrusionPath->pack(polyline => $_, role => EXTR_ROLE_PERIMETER);
-            }
-            $thin_paths[-1]->flow_spacing($self->perimeters_flow->spacing);
+            push @thin_paths, $_->isa('Slic3r::Polygon')
+                ? Slic3r::ExtrusionLoop->pack(polygon => $_, %properties)
+                : Slic3r::ExtrusionPath->pack(polyline => $_, %properties);
         }
         my $collection = Slic3r::ExtrusionPath::Collection->new(paths => \@thin_paths);
         push @{ $self->perimeters }, $collection->shortest_path;
diff --git a/lib/Slic3r/Print.pm b/lib/Slic3r/Print.pm
index 22e9002e..ac4a195b 100644
--- a/lib/Slic3r/Print.pm
+++ b/lib/Slic3r/Print.pm
@@ -604,8 +604,12 @@ sub write_gcode {
             $gcode .= $gcodegen->set_tool($Slic3r::infill_extruder-1);
             $gcode .= $gcodegen->set_acceleration($Slic3r::infill_acceleration);
             for my $fill (@{ $layer->fills }) {
-                $gcode .= $gcodegen->extrude($_, 'fill') 
-                    for $fill->shortest_path($gcodegen->last_pos);
+                if ($fill->isa('Slic3r::ExtrusionPath::Collection')) {
+                    $gcode .= $gcodegen->extrude($_, 'fill') 
+                        for $fill->shortest_path($gcodegen->last_pos);
+                } else {
+                    $gcode .= $gcodegen->extrude($fill, 'fill') ;
+                }
             }
             
             # extrude support material