Backported from glibc.
Signed-off-by: Stijn Tintel <stijn@linux-ipv6.be>
--- /dev/null
+--- a/argp-help.c
++++ b/argp-help.c
+@@ -777,9 +777,9 @@ hol_entry_cmp (const struct hol_entry *e
+ const char *long2 = hol_entry_first_long (entry2);
+
+ if (doc1)
+- doc1 = canon_doc_option (&long1);
++ doc1 = long1 != NULL && canon_doc_option (&long1);
+ if (doc2)
+- doc2 = canon_doc_option (&long2);
++ doc2 = long2 != NULL && canon_doc_option (&long2);
+
+ if (doc1 != doc2)
+ /* `documentation' options always follow normal options (or