sparkline: show error if php does not run

diff --git a/IkiWiki/Plugin/sparkline.pm b/IkiWiki/Plugin/sparkline.pm
index c1f016ffd0e7055bae3f5ba72f9f04b643285c01..fb4849492eb0e20aad9045bae2d51902885abfb5 100644 (file)
--- a/IkiWiki/Plugin/sparkline.pm
+++ b/IkiWiki/Plugin/sparkline.pm
@@ -149,7 +149,7 @@ sub preprocess (@) {
 
                waitpid $pid, 0;
                $SIG{PIPE}="DEFAULT";
-               if ($sigpipe) {
+               if ($sigpipe || ! defined $png) {
                        error gettext("failed to run php");
                }