Fixed BUG#13941: replace() string fuction behaves badly inside stored

                 procedure
  For some functions returning strings (like "replace" and "ifnull" - where
  val_str() is returning a pointer into one of the parameters) - we ended
  up with a dangling pointer after the new operator destroyed the reuse item
  in the eval function.
  A working, if not very elegant, solution is to simply copy the string in
  such cases.


mysql-test/r/sp.result:
  New test case for BUG#13941.
mysql-test/t/sp.test:
  New test case for BUG#13941.
sql/sp_head.cc:
  Copy the string when evaluating some string functions (e.g. "replace" and "ifnull")
  to avoid using a dangling pointer.

1 files changed, 43 insertions, 0 deletions

diff --git a/mysql-test/t/sp.test b/mysql-test/t/sp.test
index 4b9987c2803..18607c7f13c 100644
--- a/mysql-test/t/sp.test
+++ b/mysql-test/t/sp.test
@@ -4391,6 +4391,49 @@ drop function bug7049_2|
 
 
 #
+# BUG#13941: replace() string fuction behaves badly inside stored procedure
+# (BUG#13914: IFNULL is returning garbage in stored procedure)
+#
+--disable_warnings
+drop function if exists bug13941|
+drop procedure if exists bug13941|
+--enable_warnings
+
+create function bug13941(p_input_str text)
+  returns text
+begin
+  declare p_output_str text;
+
+  set p_output_str = p_input_str;
+
+  set p_output_str = replace(p_output_str, 'xyzzy', 'plugh');
+  set p_output_str = replace(p_output_str, 'test', 'prova');
+  set p_output_str = replace(p_output_str, 'this', 'questo');
+  set p_output_str = replace(p_output_str, ' a ', 'una ');
+  set p_output_str = replace(p_output_str, 'is', '');
+
+  return p_output_str;
+end|
+
+create procedure bug13941(out sout varchar(128))
+begin
+  set sout = 'Local';
+  set sout = ifnull(sout, 'DEF');
+end|
+
+# Note: The bug showed different behaviour in different types of builds,
+#  giving garbage results in some, and seemingly working in others.
+#  Running with valgrind (or purify) is the safe way to check that it's
+#  really working correctly.
+select bug13941('this is a test')|
+call bug13941(@a)|
+select @a|
+
+drop function bug13941|
+drop procedure bug13941|
+
+
+#
 # BUG#NNNN: New bug synopsis
 #
 #--disable_warnings