Fix unportable usage associated with va_list arguments.  Passing "0" to

a va_list argument only works if va_list is an integer or pointer type,

which is not required by the C spec, and is not true on ARM for instance.

Per bug #744707.

diff -Naur mysql-5.5.16.orig/sql-common/client_plugin.c mysql-5.5.16/sql-common/client_plugin.c

--- mysql-5.5.16.orig/sql-common/client_plugin.c	2011-09-09 11:56:39.000000000 -0400

+++ mysql-5.5.16/sql-common/client_plugin.c	2011-10-16 23:00:00.708799138 -0400

@@ -233,11 +233,13 @@

 {

   MYSQL mysql;

   struct st_mysql_client_plugin **builtin;

+  va_list unused;

   if (initialized)

     return 0;

   bzero(&mysql, sizeof(mysql)); /* dummy mysql for set_mysql_extended_error */

+  bzero(&unused, sizeof(unused)); /* suppress uninitialized-value warnings */

   pthread_mutex_init(&LOCK_load_client_plugin, MY_MUTEX_INIT_SLOW);

   init_alloc_root(&mem_root, 128, 128);

@@ -249,7 +251,7 @@

   pthread_mutex_lock(&LOCK_load_client_plugin);

   for (builtin= mysql_client_builtins; *builtin; builtin++)

-    add_plugin(&mysql, *builtin, 0, 0, 0);

+    add_plugin(&mysql, *builtin, 0, 0, unused);

   pthread_mutex_unlock(&LOCK_load_client_plugin);

@@ -293,9 +295,13 @@

 mysql_client_register_plugin(MYSQL *mysql,

                              struct st_mysql_client_plugin *plugin)

 {

+  va_list unused;

+

   if (is_not_initialized(mysql, plugin->name))

     return NULL;

+  bzero(&unused, sizeof(unused)); /* suppress uninitialized-value warnings */

+

   pthread_mutex_lock(&LOCK_load_client_plugin);

   /* make sure the plugin wasn't loaded meanwhile */

@@ -307,7 +313,7 @@

     plugin= NULL;

   }

   else

-    plugin= add_plugin(mysql, plugin, 0, 0, 0);

+    plugin= add_plugin(mysql, plugin, 0, 0, unused);

   pthread_mutex_unlock(&LOCK_load_client_plugin);

   return plugin;