+sub calculate_changed_links ($$$) {
+ my ($changed, $del, $oldlink_targets)=@_;
+
+ my (%backlinkchanged, %linkchangers);
+
+ foreach my $file (@$changed, @$del) {
+ my $page=pagename($file);
+
+ if (exists $links{$page}) {
+ foreach my $l (@{$links{$page}}) {
+ my $target=bestlink($page, $l);
+ if (! exists $oldlink_targets->{$page}{$l} ||
+ $target ne $oldlink_targets->{$page}{$l}) {
+ $backlinkchanged{$target}=1;
+ $linkchangers{lc($page)}=1;
+ }
+ delete $oldlink_targets->{$page}{$l};
+ }
+ }
+ if (exists $oldlink_targets->{$page} &&
+ %{$oldlink_targets->{$page}}) {
+ foreach my $target (values %{$oldlink_targets->{$page}}) {
+ $backlinkchanged{$target}=1;
+ }
+ $linkchangers{lc($page)}=1;
+ }
+
+ # we currently assume that changing the type of a link doesn't
+ # change backlinks
+ if (!exists $linkchangers{lc($page)}) {
+ if (link_types_changed($typedlinks{$page}, $oldtypedlinks{$page})) {
+ $linkchangers{lc($page)}=1;
+ }
+ }
+ }
+
+ return \%backlinkchanged, \%linkchangers;
+}
+
+sub render_dependent ($$$$$$$) {
+ my ($files, $new, $internal_new, $del, $internal_del,
+ $internal_changed, $linkchangers)=@_;
+
+ my @changed=(keys %rendered, @$del);
+ my @exists_changed=(@$new, @$del);