Bug#11835 CREATE FUNCTION crashes server

 - Update for 5.1
 - Add "have_dlopen"
 - Remove requirement to load udf's only in "opt_plugin_dir" 


include/my_global.h:
  Remove duplicate defines
mysql-test/include/have_udf.inc:
  Use "have_dlopen" to check if we "have udf"
mysql-test/r/have_udf.require:
  Use "have_dlopen" to check if we "have udf"
mysql-test/r/udf.result:
  Update for new error message "function"->"symbol"
sql/item_func.cc:
  Remove "evil" dbug printour that checks args[0] even if arg_count is 0
sql/mysql_priv.h:
  Add "have_dlopen"
sql/mysqld.cc:
  Add "have_dlopen"
  Move HAVE_DLOPEN defined to only surround "udf_free" and "udf_init"
sql/set_var.cc:
  Add "have_dlopen"
sql/sql_plugin.cc:
  Surround 'dlclose' with HAVE_DLOPEN
sql/sql_udf.cc:
  Remove the requirement to load udf's only from "opt_plugin_dir".
  Fix spelling error

1 files changed, 2 insertions, 0 deletions

diff --git a/sql/sql_plugin.cc b/sql/sql_plugin.cc
index ad99d81d7b4..74852716f74 100644
--- a/sql/sql_plugin.cc
+++ b/sql/sql_plugin.cc
@@ -94,8 +94,10 @@ static st_plugin_dl *plugin_dl_insert_or_reuse(struct st_plugin_dl *plugin_dl)
 
 static inline void free_plugin_mem(struct st_plugin_dl *p)
 {
+#ifdef HAVE_DLOPEN
   if (p->handle)
     dlclose(p->handle);
+#endif
   my_free(p->dl.str, MYF(MY_ALLOW_ZERO_PTR));
   if (p->version != MYSQL_PLUGIN_INTERFACE_VERSION)
     my_free((gptr)p->plugins, MYF(MY_ALLOW_ZERO_PTR));