Include stdarg.h for va_list in xmalloc.h.

match.c

@@ -40,6 +40,7 @@
 #include <sys/types.h>
 
 #include <ctype.h>
+#include <stdarg.h>
 #include <stdlib.h>
 #include <string.h>
 #include <stdio.h>

sftp-glob.c

@@ -23,6 +23,7 @@
 #endif
 
 #include <dirent.h>
+#include <stdarg.h>
 #include <stdlib.h>
 #include <string.h>
 

umac.c

@@ -74,6 +74,7 @@
 #include "includes.h"
 #include <sys/types.h>
 #include <string.h>
+#include <stdarg.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <stddef.h>