Bug#48449: hang on show create view after upgrading when view contains function of view

SHOW CREATE TABLE on a view (v1) that contains a function whose
statement uses another view (v2), could trigger a infinite loop
if the view referenced within the function causes a warning to
be raised while opening the said view (v2).

The problem was a infinite loop over the stack of internal error
handlers. The problem would be triggered if the stack contained
two or more handlers and the first two handlers didn't handle the
raised condition. In this case, the loop variable would always
point to the second handler in the stack.

The solution is to correct the loop variable assignment so that
the loop is able to iterate over all handlers in the stack.

mysql-test/r/view.result:
  Add test case result for Bug#48449.
mysql-test/std_data/bug48449.frm:
  Add a incomplete view definition that causes a warning to be
  issued.
mysql-test/t/view.test:
  Add test case for Bug#48449
sql/sql_class.cc:
  Iterate over all handlers in the stack.

1 files changed, 12 insertions, 0 deletions

diff --git a/mysql-test/std_data/bug48449.frm b/mysql-test/std_data/bug48449.frm
new file mode 100644
index 00000000000..b6a717427aa
--- /dev/null
+++ b/mysql-test/std_data/bug48449.frm
@@ -0,0 +1,12 @@
+TYPE=VIEW
+query=select `test`.`t2`.`a` AS `a` from `test`.`t2`
+md5=5e6eaf216e7b016fcedfd4e1113517af
+updatable=1
+algorithm=0
+definer_user=root
+definer_host=localhost
+suid=2
+with_check_option=0
+timestamp=2010-01-01 15:00:00
+create-version=1
+source=select * from t2