diff --git a/mysql-test/r/keywords.result b/mysql-test/r/keywords.result
index 597983dab7e..e4c83b21138 100644
--- a/mysql-test/r/keywords.result
+++ b/mysql-test/r/keywords.result
@@ -16,6 +16,19 @@ select events.binlog from events;
 binlog
 1
 drop table events;
+create table t1 (connection int, b int);
+create procedure p1()
+begin
+declare connection int;
+select max(t1.connection) into connection from t1;
+select concat("max=",connection) 'p1';
+end|
+insert into t1 (connection) values (1);
+call p1();
+p1
+max=1
+drop procedure p1;
+drop table t1;
 create procedure p1()
 begin
 declare n int default 2;
diff --git a/mysql-test/t/keywords.test b/mysql-test/t/keywords.test
index 1af4a1354be..afc7fb55d51 100644
--- a/mysql-test/t/keywords.test
+++ b/mysql-test/t/keywords.test
@@ -20,6 +20,28 @@ drop table events;
 
 # End of 4.1 tests
 
+
+#
+# Bug#12204 - CONNECTION should not be a reserved word
+#
+
+create table t1 (connection int, b int);
+delimiter |;
+create procedure p1()
+begin
+  declare connection int;
+  select max(t1.connection) into connection from t1;
+  select concat("max=",connection) 'p1';
+end|
+delimiter ;|
+insert into t1 (connection) values (1);
+call p1();
+drop procedure p1;
+drop table t1;
+
+
+# End of 5.0 tests
+
 #
 # Bug#19939 "AUTHORS is not a keyword"
 #
diff --git a/mysys/my_thr_init.c b/mysys/my_thr_init.c
index 853a2761224..de926a1e969 100644
--- a/mysys/my_thr_init.c
+++ b/mysys/my_thr_init.c
@@ -46,6 +46,8 @@ pthread_mutexattr_t my_fast_mutexattr;
 pthread_mutexattr_t my_errorcheck_mutexattr;
 #endif
 
+uint thd_lib_detected;
+
 #ifdef NPTL_PTHREAD_EXIT_BUG /* see my_pthread.h */
 
 /*
diff --git a/sql/sql_yacc.yy b/sql/sql_yacc.yy
index 424fd98c4fc..aa386dcf09c 100644
--- a/sql/sql_yacc.yy
+++ b/sql/sql_yacc.yy
@@ -9667,6 +9667,7 @@ keyword_sp:
 	| COMPLETION_SYM	{}
 	| COMPRESSED_SYM	{}
 	| CONCURRENT		{}
+	| CONNECTION_SYM	{}
 	| CONSISTENT_SYM	{}
 	| CONTRIBUTORS_SYM	{}
 	| CUBE_SYM		{}