Fixed on BUG#6048: Stored procedure causes operating system reboot

  Memory leak in locally evalutated expressions during SP execution fixed by
  reusing allocated item slots when possible.
  Note: No test case added, since the test is a stress test that tries to make
  the machine to run out of memory.
  Second attempt, now tested with debug build, valgrind build, max (optimized)
  build, with and without --debug, --vagrind and --ps-protocol.
  Errors in trigger and view test with --debug in debug build where present
  before this patch, and likewise for valgrind warnings for view test in
  valgrind build with --ps-protocol.


sql/item.cc:
  Init rsize in Item (for SP item reusal).
sql/item.h:
  Addes special new operator for reuse of Items, for SP internal use only.
sql/sp_head.cc:
  Reuse items assigned internally in SPs when possible.
sql/sp_rcontext.cc:
  Reuse items assigned internally in SPs when possible.
  Moved the local variable assignment here (from sp_head) to avoid
  duplicated code.
sql/sp_rcontext.h:
  New arg to sp_rcontext::set_item_eval() (and some coding style).
sql/sql_class.cc:
  Adjusted call to new set_item_eval().

1 files changed, 3 insertions, 4 deletions

diff --git a/sql/sp_rcontext.h b/sql/sp_rcontext.h
index c132032e32c..417c50d0f0f 100644
--- a/sql/sp_rcontext.h
+++ b/sql/sp_rcontext.h
@@ -62,19 +62,19 @@ class sp_rcontext : public Sql_alloc
   push_item(Item *i)
   {
     if (m_count < m_fsize)
-      m_frame[m_count++] = i;
+      m_frame[m_count++]= i;
   }
 
   inline void
   set_item(uint idx, Item *i)
   {
     if (idx < m_count)
-      m_frame[idx] = i;
+      m_frame[idx]= i;
   }
 
   /* Returns 0 on success, -1 on (eval) failure */
   int
-  set_item_eval(uint idx, Item **i, enum_field_types type);
+  set_item_eval(THD *thd, uint idx, Item **i, enum_field_types type);
 
   inline Item *
   get_item(uint idx)
@@ -82,7 +82,6 @@ class sp_rcontext : public Sql_alloc
     return m_frame[idx];
   }
 
-
   inline Item **
   get_item_addr(uint idx)
   {