A patch for Bug#48915 (After having switched off the ipv6 support in OS,

mysqld crashed in network_init()).

The problem was that current_thd was not ready at that point in mysqld life,
so ER() macro could not be used.

The fix is to use ER_DEFAULT() macro, which is intented for such cases.

sql/mysqld.cc

@@ -1670,7 +1670,7 @@ static void network_init(void)
     if (error != 0)
     {
       DBUG_PRINT("error",("Got error: %d from getaddrinfo()", error));
-      sql_perror(ER(ER_IPSOCK_ERROR));		/* purecov: tested */
+      sql_perror(ER_DEFAULT(ER_IPSOCK_ERROR));  /* purecov: tested */
       unireg_abort(1);				/* purecov: tested */
     }
 
@@ -1684,7 +1684,7 @@ static void network_init(void)
     if (ip_sock == INVALID_SOCKET)
     {
       DBUG_PRINT("error",("Got error: %d from socket()",socket_errno));
-      sql_perror(ER(ER_IPSOCK_ERROR));		/* purecov: tested */
+      sql_perror(ER_DEFAULT(ER_IPSOCK_ERROR));  /* purecov: tested */
       unireg_abort(1);				/* purecov: tested */
     }