cups-pdf/SOURCES/cups-pdf-build.patch

--- src/cups-pdf.c.orig	2017-02-27 19:06:28.369835445 -0400
+++ src/cups-pdf.c	2017-02-27 19:08:14.263593153 -0400
@@ -374,6 +374,7 @@
   (void) umask(0077);
 
   group=getgrnam(Conf_Grp);
+  if (group)
     grpstat=setgid(group->gr_gid);
 
   if (strlen(Conf_Log)) {