Bug#36446: Attempt to set @@join_buffer_size to its minimum value produces spurious warning

If a sys-var has a base and a block-size>1, and then a
user-supplied value >= minimum ended up below minimum
thanks to block-size alignment, we threw a warning.
This meant for instance that when getting, then setting
the minimum, we'd see a warning. This was needlessly
confusing. (updated patch)

1 files changed, 7 insertions, 0 deletions

diff --git a/mysql-test/r/variables.result b/mysql-test/r/variables.result
index 7c9a9145ad1..f27d0b9fdd5 100644
--- a/mysql-test/r/variables.result
+++ b/mysql-test/r/variables.result
@@ -27,6 +27,7 @@ set @my_slow_launch_time          =@@global.slow_launch_time;
 set @my_storage_engine            =@@global.storage_engine;
 set @my_thread_cache_size         =@@global.thread_cache_size;
 set @my_max_allowed_packet        =@@global.max_allowed_packet;
+set @my_join_buffer_size          =@@global.join_buffer_size;
 set @`test`=1;
 select @test, @`test`, @TEST, @`TEST`, @"teSt";
 @test	@`test`	@TEST	@`TEST`	@"teSt"
@@ -1018,6 +1019,11 @@ show variables like 'hostname';
 Variable_name	Value
 hostname	#
 End of 5.0 tests
+set join_buffer_size=1;
+Warnings:
+Warning	1292	Truncated incorrect join_buffer_size value: '1'
+set @save_join_buffer_size=@@join_buffer_size;
+set join_buffer_size=@save_join_buffer_size;
 set global binlog_cache_size         =@my_binlog_cache_size;
 set global connect_timeout           =@my_connect_timeout;
 set global delayed_insert_timeout    =@my_delayed_insert_timeout;
@@ -1048,6 +1054,7 @@ set global slow_launch_time          =@my_slow_launch_time;
 set global storage_engine            =@my_storage_engine;
 set global thread_cache_size         =@my_thread_cache_size;
 set global max_allowed_packet        =@my_max_allowed_packet;
+set global join_buffer_size          =@my_join_buffer_size;
 show global variables where Variable_name='table_definition_cache' or
 Variable_name='table_lock_wait_timeout';
 Variable_name	Value