diff -rup a/hijri/src/demo_hijri.c b/hijri/src/demo_hijri.c

--- a/hijri/src/demo_hijri.c	2009-03-08 17:55:11.000000000 -0400

+++ b/hijri/src/demo_hijri.c	2023-02-15 16:10:43.759285213 -0500

@@ -23,6 +23,7 @@

  ************************************************************************/

 #include <stdio.h>

+#include <stdlib.h>

 #include <time.h>               /* for time_t */

 #include "hijri.h"

diff -rup a/hijri/src/hijri.c b/hijri/src/hijri.c

--- a/hijri/src/hijri.c	2009-03-08 17:55:22.000000000 -0400

+++ b/hijri/src/hijri.c	2023-02-15 14:47:03.794285625 -0500

@@ -109,6 +109,10 @@ char *h_month_short[13] = {"skip",

 			   "Ram", "Sha", "Qid", "Hij"};

+/* Forward declarations for C99 compatibility.  */

+int g_absolute(int day, int month, int year);

+int g_numdays(int month, int year);

+

 /* Store-off any events for passed-in date */

 int

 get_events(char ***addr_event,

diff -rup a/hijri/src/umm_alqura.c b/hijri/src/umm_alqura.c

--- a/hijri/src/umm_alqura.c	2009-03-08 17:55:45.000000000 -0400

+++ b/hijri/src/umm_alqura.c	2023-02-15 16:08:27.002858747 -0500

@@ -81,6 +81,11 @@ double ip(double x);

 int mod(double x, double y);

 int IsValid(int yh, int mh, int dh);

+int fill_datestruct(sDate *fdate, int weekday, int frm_month_num,

+		    int to_month_num, char *frm_day[], char *frm_day_short[],

+		    char *frm_month[], char *frm_month_short[], char *to_day[],

+		    char *to_day_short[], char *to_month[],

+		    char *to_month_short[], sEvent *farr_table, int farr_size);

 /****************************************************************************/

 /* Name:    Hsub2G                                                          */