https://bugs.gentoo.org/503954

fix build w/readline-6.3

patch by Martin von Gagern

--- mailutils-2.99.98/mu/shell.c
+++ mailutils-2.99.98/mu/shell.c
@@ -336,7 +336,7 @@ mutool_initialize_readline (const char *
 {
   /* Allow conditional parsing of the ~/.inputrc file. */
   rl_readline_name = (char *) name;
-  rl_attempted_completion_function = (CPPFunction *) shell_completion;
+  rl_attempted_completion_function = shell_completion;
   rl_getc_function = _shell_getc;
   read_history (get_history_file_name ());
 }
--- mailutils-2.99.98/mail/mailline.c
+++ mailutils-2.99.98/mail/mailline.c
@@ -93,7 +93,7 @@ ml_readline_init ()
 
 #ifdef WITH_READLINE
   rl_readline_name = "mail";
-  rl_attempted_completion_function = (CPPFunction*)ml_command_completion;
+  rl_attempted_completion_function = ml_command_completion;
   rl_getc_function = ml_getc;
 #endif
 #ifdef HAVE_SIGACTION
--- mailutils-2.99.98/examples/nntpclient.c
+++ mailutils-2.99.98/examples/nntpclient.c
@@ -163,7 +163,7 @@ initialize_readline ()
   rl_readline_name = (char *) "nntp";
 
   /* Tell the completer that we want a crack first. */
-  rl_attempted_completion_function = (CPPFunction *) nntp_completion;
+  rl_attempted_completion_function = nntp_completion;
 }
 
 /* Attempt to complete on the contents of TEXT.  START and END bound the