Auto-merge from mysql-trunk-bugfixing.

******
This patch fixes the following bugs:
  - Bug#5889: Exit handler for a warning doesn't hide the warning in
    trigger
  - Bug#9857: Stored procedures: handler for sqlwarning ignored
  - Bug#23032: Handlers declared in a SP do not handle warnings generated
    in sub-SP
  - Bug#36185: Incorrect precedence for warning and exception handlers

The problem was in the way warnings/errors during stored routine execution
were handled. Prior to this patch the logic was as follows:

  - when a warning/an error happens: if we're executing a stored routine,
    and there is a handler for that warning/error, remember the handler,
    ignore the warning/error and continue execution.

  - after a stored routine instruction is executed: check for a remembered
    handler and activate one (if any).

This logic caused several problems:

  - if one instruction generates several warnings (errors) it's impossible
    to choose the right handler -- a handler for the first generated
    condition was chosen and remembered for activation.

  - mess with handling conditions in scopes different from the current one.

  - not putting generated warnings/errors into Warning Info (Diagnostic
    Area) is against The Standard.

The patch changes the logic as follows:

  - Diagnostic Area is cleared on the beginning of each statement that
    either is able to generate warnings, or is able to work with tables.

  - at the end of a stored routine instruction, Diagnostic Area is left
    intact.

  - Diagnostic Area is checked after each stored routine instruction. If
    an instruction generates several condition, it's now possible to take a
    look at all of them and determine an appropriate handler.

mysql-test/r/signal.result:
  Update result file:
    1. handled conditions are not cleared any more;
    2. reflect changes in signal.test
mysql-test/r/signal_demo3.result:
  Update result file: handled conditions are not cleared any more.
  Due to playing with max_error_count, resulting warning lists
  have changed.
mysql-test/r/sp-big.result:
  Update result file: handled conditions are not cleared any more.
mysql-test/r/sp-bugs.result:
  Update result file: handled conditions are not cleared any more.
mysql-test/r/sp-code.result:
  Update result file:
    1. handled conditions are not cleared any more.
    2. add result for a new test case in sp-code.test.
mysql-test/r/sp-error.result:
  Update result file:
    1. handled conditions are not cleared any more.
    2. add result for a new test case in sp-error.test.
mysql-test/r/sp.result:
  Update result file: handled conditions are not cleared any more.
mysql-test/r/sp_trans.result:
  Update result file: handled conditions are not cleared any more.
mysql-test/r/strict.result:
  Update result file: handled conditions are not cleared any more.
mysql-test/r/view.result:
  Update result file: handled conditions are not cleared any more.
mysql-test/suite/funcs_1/r/innodb_storedproc_02.result:
  Update result file: handled conditions are not cleared any more.
mysql-test/suite/funcs_1/r/memory_storedproc_02.result:
  Update result file: handled conditions are not cleared any more.
mysql-test/suite/funcs_1/r/myisam_storedproc_02.result:
  Update result file: handled conditions are not cleared any more.
mysql-test/suite/funcs_1/r/storedproc.result:
  Update result file: handled conditions are not cleared any more.
mysql-test/suite/rpl/r/rpl_row_sp005.result:
  Update result file: handled conditions are not cleared any more.
mysql-test/suite/rpl/r/rpl_row_sp006_InnoDB.result:
  Update result file: handled conditions are not cleared any more.
mysql-test/suite/rpl/r/rpl_row_trig003.result:
  Update result file: handled conditions are not cleared any more.
mysql-test/t/signal.test:
  Make a test case more readable in the result file.
mysql-test/t/sp-code.test:
  Add a test case for Bug#23032 checking that
  No Data takes precedence on Warning.
mysql-test/t/sp-error.test:
  Adding test cases for:
    - Bug#23032
    - Bug#36185
    - Bug#5889
    - Bug#9857
mysql-test/t/sp.test:
  Fixing test case to reflect behavioral changes made by the patch.
sql/sp_head.cc:
  Reset the per-statement warning count before executing
  a stored procedure instruction.
  
  Move to a separate function code which checks the
  completion status of the executed statement and searches
  for a handler.
  
  Remove redundant code now that search for a handler is
  done after execution, errors are always pushed.
sql/sp_pcontext.h:
  Remove unused code.
sql/sp_rcontext.cc:
  - Polish sp_rcontext::find_handler(): use sp_rcontext::m_hfound instead
    of an extra local variable;
  
  - Remove sp_rcontext::handle_condition();
  
  - Introduce sp_rcontext::activate_handler(), which prepares
    previously found handler for execution.
  
  - Move sp_rcontext::enter_handler() code into activate_handler(),
    because enter_handler() is used only from there;
  
  - Cleanups;
  
  - Introduce DBUG_EXECUTE_IF() for a test case in sp-code.test
sql/sp_rcontext.h:
  - Remove unused code
  - Cleanups
sql/sql_class.cc:
  Merge THD::raise_condition_no_handler() into THD::raise_condition().
  After the patch raise_condition_no_handler() was called
  in raise_condition() only.
sql/sql_class.h:
  Remove raise_condition_no_handler().
sql/sql_error.cc:
  Remove Warning_info::reserve_space() -- handled conditions are not
  cleared any more, so there is no need for RESIGNAL to re-push them.
sql/sql_error.h:
  Remove Warning_info::reserve_space().
sql/sql_signal.cc:
  Handled conditions are not cleared any more,
  so there is no need for RESIGNAL to re-push them.

9 files changed, 277 insertions, 314 deletions

diff --git a/sql/sp_head.cc b/sql/sp_head.cc
index 11f138e67be..2d3a32c7f7f 100644
--- a/sql/sp_head.cc
+++ b/sql/sp_head.cc
@@ -1076,6 +1076,104 @@ void sp_head::recursion_level_error(THD *thd)
 
 
 /**
+  Find an SQL handler for any condition (warning or error) after execution
+  of a stored routine instruction. Basically, this function looks for an
+  appropriate SQL handler in RT-contexts. If an SQL handler is found, it is
+  remembered in the RT-context for future activation (the context can be
+  inactive at the moment).
+
+  If there is no pending condition, the function just returns.
+
+  If there was an error during the execution, an SQL handler for it will be
+  searched within the current and outer scopes.
+
+  There might be several errors in the Warning Info (that's possible by using
+  SIGNAL/RESIGNAL in nested scopes) -- the function is looking for an SQL
+  handler for the latest (current) error only.
+
+  If there was a warning during the execution, an SQL handler for it will be
+  searched within the current scope only.
+
+  If several warnings were thrown during the execution and there are different
+  SQL handlers for them, it is not determined which SQL handler will be chosen.
+  Only one SQL handler will be executed.
+
+  If warnings and errors were thrown during the execution, the error takes
+  precedence. I.e. error handler will be executed. If there is no handler
+  for that error, condition will remain unhandled.
+
+  Once a warning or an error has been handled it is not removed from
+  Warning Info.
+
+  According to The Standard (quoting PeterG):
+
+    An SQL procedure statement works like this ...
+    SQL/Foundation 13.5 <SQL procedure statement>
+    (General Rules) (greatly summarized) says:
+    (1) Empty diagnostics area, thus clearing the condition.
+    (2) Execute statement.
+        During execution, if Exception Condition occurs,
+        set Condition Area = Exception Condition and stop
+        statement.
+        During execution, if No Data occurs,
+        set Condition Area = No Data Condition and continue
+        statement.
+        During execution, if Warning occurs,
+        and Condition Area is not already full due to
+        an earlier No Data condition, set Condition Area
+        = Warning and continue statement.
+    (3) Finish statement.
+        At end of execution, if Condition Area is not
+        already full due to an earlier No Data or Warning,
+        set Condition Area = Successful Completion.
+        In effect, this system means there is a precedence:
+        Exception trumps No Data, No Data trumps Warning,
+        Warning trumps Successful Completion.
+
+    NB: "Procedure statements" include any DDL or DML or
+    control statements. So CREATE and DELETE and WHILE
+    and CALL and RETURN are procedure statements. But
+    DECLARE and END are not procedure statements.
+
+  @param thd thread handle
+  @param ctx runtime context of the stored routine
+*/
+
+static void
+find_handler_after_execution(THD *thd, sp_rcontext *ctx)
+{
+  if (thd->is_error())
+  {
+    ctx->find_handler(thd,
+                      thd->stmt_da->sql_errno(),
+                      thd->stmt_da->get_sqlstate(),
+                      MYSQL_ERROR::WARN_LEVEL_ERROR,
+                      thd->stmt_da->message());
+  }
+  else if (thd->warning_info->statement_warn_count())
+  {
+    List_iterator<MYSQL_ERROR> it(thd->warning_info->warn_list());
+    MYSQL_ERROR *err;
+    while ((err= it++))
+    {
+      if (err->get_level() != MYSQL_ERROR::WARN_LEVEL_WARN &&
+          err->get_level() != MYSQL_ERROR::WARN_LEVEL_NOTE)
+        continue;
+
+      if (ctx->find_handler(thd,
+                            err->get_sql_errno(),
+                            err->get_sqlstate(),
+                            err->get_level(),
+                            err->get_message_text()))
+      {
+        break;
+      }
+    }
+  }
+}
+
+
+/**
   Execute the routine. The main instruction jump loop is there.
   Assume the parameters already set.
   @todo
@@ -1096,7 +1194,7 @@ sp_head::execute(THD *thd)
   LEX_STRING saved_cur_db_name=
     { saved_cur_db_name_buf, sizeof(saved_cur_db_name_buf) };
   bool cur_db_changed= FALSE;
-  sp_rcontext *ctx;
+  sp_rcontext *ctx= thd->spcont;
   bool err_status= FALSE;
   uint ip= 0;
   ulong save_sql_mode;
@@ -1157,8 +1255,6 @@ sp_head::execute(THD *thd)
     goto done;
   }
 
-  if ((ctx= thd->spcont))
-    ctx->clear_handler();
   thd->is_slave_error= 0;
   old_arena= thd->stmt_arena;
 
@@ -1243,7 +1339,6 @@ sp_head::execute(THD *thd)
   do
   {
     sp_instr *i;
-    uint hip;
 
 #if defined(ENABLED_PROFILING)
     /*
@@ -1265,6 +1360,9 @@ sp_head::execute(THD *thd)
       break;
     }
 
+    /* Reset number of warnings for this query. */
+    thd->warning_info->reset_for_next_command();
+
     DBUG_PRINT("execute", ("Instruction %u", ip));
 
     /*
@@ -1309,40 +1407,28 @@ sp_head::execute(THD *thd)
     free_root(&execute_mem_root, MYF(0));
 
     /*
-      Check if an exception has occurred and a handler has been found
-      Note: We have to check even if err_status == FALSE, since warnings (and
-      some errors) don't return a non-zero value. We also have to check even
-      if thd->killed != 0, since some errors return with this even when a
-      handler has been found (e.g. "bad data").
+      Find and process SQL handlers unless it is a fatal error (fatal
+      errors are not catchable by SQL handlers) or the connection has been
+      killed during execution.
     */
-    if (ctx)
+    if (!thd->is_fatal_error && !thd->killed_errno())
     {
-      uint handler_index;
+      /*
+        Find SQL handler in the appropriate RT-contexts:
+          - warnings can be handled by SQL handlers within
+            the current scope only;
+          - errors can be handled by any SQL handler from outer scope.
+      */
+      find_handler_after_execution(thd, ctx);
 
-      switch (ctx->found_handler(& hip, & handler_index)) {
-      case SP_HANDLER_NONE:
-        break;
-      case SP_HANDLER_CONTINUE:
-        thd->restore_active_arena(&execute_arena, &backup_arena);
-        thd->set_n_backup_active_arena(&execute_arena, &backup_arena);
-        ctx->push_hstack(i->get_cont_dest());
-        /* Fall through */
-      default:
-        if (ctx->end_partial_result_set)
-          thd->protocol->end_partial_result_set(thd);
-        ip= hip;
+      /* If found, activate handler for the current scope. */
+      if (ctx->activate_handler(thd, &ip, i, &execute_arena, &backup_arena))
         err_status= FALSE;
-        ctx->clear_handler();
-        ctx->enter_handler(hip, handler_index);
-        thd->clear_error();
-        thd->is_fatal_error= 0;
-        thd->killed= THD::NOT_KILLED;
-        thd->mysys_var->abort= 0;
-        continue;
-      }
-
-      ctx->end_partial_result_set= FALSE;
     }
+
+    /* Reset sp_rcontext::end_partial_result_set flag. */
+    ctx->end_partial_result_set= FALSE;
+
   } while (!err_status && !thd->killed && !thd->is_fatal_error);
 
 #if defined(ENABLED_PROFILING)
@@ -3037,23 +3123,14 @@ sp_instr_set::exec_core(THD *thd, uint *nextp)
 {
   int res= thd->spcont->set_variable(thd, m_offset, &m_value);
 
-  if (res && thd->spcont->found_handler_here())
+  if (res)
   {
-    /*
-      Failed to evaluate the value, and a handler has been found. Reset the
-      variable to NULL.
-    */
+    /* Failed to evaluate the value. Reset the variable to NULL. */
 
     if (thd->spcont->set_variable(thd, m_offset, 0))
     {
       /* If this also failed, let's abort. */
-
-      sp_rcontext *spcont= thd->spcont;
-
-      thd->spcont= NULL;           /* Avoid handlers */
-      my_error(ER_OUT_OF_RESOURCES, MYF(0));
-      spcont->clear_handler();
-      thd->spcont= spcont;
+      my_error(ER_OUT_OF_RESOURCES, MYF(ME_FATALERROR));
     }
   }
 
@@ -3586,18 +3663,6 @@ sp_instr_copen::execute(THD *thd, uint *nextp)
     if (thd->stmt_arena->free_list)
       cleanup_items(thd->stmt_arena->free_list);
     thd->stmt_arena= old_arena;
-    /*
-      Work around the fact that errors in selects are not returned properly
-      (but instead converted into a warning), so if a condition handler
-      caught, we have lost the result code.
-    */
-    if (!res)
-    {
-      uint dummy1, dummy2;
-
-      if (thd->spcont->found_handler(&dummy1, &dummy2))
-        res= -1;
-    }
     /* TODO: Assert here that we either have an error or a cursor */
   }
   DBUG_RETURN(res);
@@ -3773,13 +3838,11 @@ sp_instr_set_case_expr::exec_core(THD *thd, uint *nextp)
 {
   int res= thd->spcont->set_case_expr(thd, m_case_expr_id, &m_case_expr);
 
-  if (res &&
-      !thd->spcont->get_case_expr(m_case_expr_id) &&
-      thd->spcont->found_handler_here())
+  if (res && !thd->spcont->get_case_expr(m_case_expr_id))
   {
     /*
       Failed to evaluate the value, the case expression is still not
-      initialized, and a handler has been found. Set to NULL so we can continue.
+      initialized. Set to NULL so we can continue.
     */
 
     Item *null_item= new Item_null();
@@ -3788,13 +3851,7 @@ sp_instr_set_case_expr::exec_core(THD *thd, uint *nextp)
         thd->spcont->set_case_expr(thd, m_case_expr_id, &null_item))
     {
       /* If this also failed, we have to abort. */
-
-      sp_rcontext *spcont= thd->spcont;
-
-      thd->spcont= NULL;           /* Avoid handlers */
-      my_error(ER_OUT_OF_RESOURCES, MYF(0));
-      spcont->clear_handler();
-      thd->spcont= spcont;
+      my_error(ER_OUT_OF_RESOURCES, MYF(ME_FATALERROR));
     }
   }
   else
diff --git a/sql/sp_pcontext.h b/sql/sp_pcontext.h
index b12d5362c6b..c27c7d22da2 100644
--- a/sql/sp_pcontext.h
+++ b/sql/sp_pcontext.h
@@ -332,13 +332,6 @@ public:
   int
   push_cond(LEX_STRING *name, sp_cond_type_t *val);
 
-  inline void
-  pop_cond(uint num)
-  {
-    while (num--)
-      pop_dynamic(&m_conds);
-  }
-
   sp_cond_type_t *
   find_cond(LEX_STRING *name, my_bool scoped=0);
 
diff --git a/sql/sp_rcontext.cc b/sql/sp_rcontext.cc
index b08f8008b59..e76a5e9ebde 100644
--- a/sql/sp_rcontext.cc
+++ b/sql/sp_rcontext.cc
@@ -171,48 +171,50 @@ sp_rcontext::set_return_value(THD *thd, Item **return_value_item)
 #define IS_NOT_FOUND_CONDITION(S) ((S)[0] == '0' && (S)[1] == '2')
 #define IS_EXCEPTION_CONDITION(S) ((S)[0] != '0' || (S)[1] > '2')
 
-/*
-  Find a handler for the given errno.
-  This is called from all error message functions (e.g. push_warning,
-  net_send_error, et al) when a sp_rcontext is in effect. If a handler
-  is found, no error is sent, and the the SP execution loop will instead
-  invoke the found handler.
-  This might be called several times before we get back to the execution
-  loop, so m_hfound can be >= 0 if a handler has already been found.
-  (In which case we don't search again - the first found handler will
-   be used.)
-  Handlers are pushed on the stack m_handler, with the latest/innermost
+/**
+  Find an SQL handler for the given error.
+
+  SQL handlers are pushed on the stack m_handler, with the latest/innermost
   one on the top; we then search for matching handlers from the top and
   down.
+
   We search through all the handlers, looking for the most specific one
   (sql_errno more specific than sqlstate more specific than the rest).
   Note that mysql error code handlers is a MySQL extension, not part of
   the standard.
 
-  SYNOPSIS
-    sql_errno     The error code
-    level         Warning level
+  SQL handlers for warnings are searched in the current scope only.
 
-  RETURN
-    1             if a handler was found, m_hfound is set to its index (>= 0)
-    0             if not found, m_hfound is -1
+  SQL handlers for errors are searched in the current and in outer scopes.
+  That's why finding and activation of handler must be separated: an errror
+  handler might be located in the outer scope, which is not active at the
+  moment. Before such handler can be activated, execution flow should
+  unwind to that scope.
+
+  Found SQL handler is remembered in m_hfound for future activation.
+  If no handler is found, m_hfound is -1.
+
+  @param thd        Thread handle
+  @param sql_errno  The error code
+  @param sqlstate   The error SQL state
+  @param level      The error level
+  @param msg        The error message
+
+  @retval TRUE  if an SQL handler was found
+  @retval FALSE otherwise
 */
 
 bool
 sp_rcontext::find_handler(THD *thd,
                           uint sql_errno,
-                          const char* sqlstate,
+                          const char *sqlstate,
                           MYSQL_ERROR::enum_warning_level level,
-                          const char* msg,
-                          MYSQL_ERROR ** cond_hdl)
+                          const char *msg)
 {
-  if (m_hfound >= 0)
-  {
-    *cond_hdl= NULL;
-    return TRUE;			// Already got one
-  }
+  int i= m_hcount;
 
-  int i= m_hcount, found= -1;
+  /* Reset previously found handler. */
+  m_hfound= -1;
 
   /*
     If this is a fatal sub-statement error, and this runtime
@@ -240,105 +242,56 @@ sp_rcontext::find_handler(THD *thd,
     {
     case sp_cond_type_t::number:
       if (sql_errno == cond->mysqlerr &&
-          (found < 0 || m_handler[found].cond->type > sp_cond_type_t::number))
-	found= i;		// Always the most specific
+          (m_hfound < 0 || m_handler[m_hfound].cond->type > sp_cond_type_t::number))
+	m_hfound= i;		// Always the most specific
       break;
     case sp_cond_type_t::state:
       if (strcmp(sqlstate, cond->sqlstate) == 0 &&
-	  (found < 0 || m_handler[found].cond->type > sp_cond_type_t::state))
-	found= i;
+	  (m_hfound < 0 || m_handler[m_hfound].cond->type > sp_cond_type_t::state))
+	m_hfound= i;
       break;
     case sp_cond_type_t::warning:
       if ((IS_WARNING_CONDITION(sqlstate) ||
            level == MYSQL_ERROR::WARN_LEVEL_WARN) &&
-          found < 0)
-	found= i;
+          m_hfound < 0)
+	m_hfound= i;
       break;
     case sp_cond_type_t::notfound:
-      if (IS_NOT_FOUND_CONDITION(sqlstate) && found < 0)
-	found= i;
+      if (IS_NOT_FOUND_CONDITION(sqlstate) && m_hfound < 0)
+	m_hfound= i;
       break;
     case sp_cond_type_t::exception:
       if (IS_EXCEPTION_CONDITION(sqlstate) &&
 	  level == MYSQL_ERROR::WARN_LEVEL_ERROR &&
-	  found < 0)
-	found= i;
+	  m_hfound < 0)
+	m_hfound= i;
       break;
     }
   }
-  if (found < 0)
-  {
-    /*
-      Only "exception conditions" are propagated to handlers in calling
-      contexts. If no handler is found locally for a "completion condition"
-      (warning or "not found") we will simply resume execution.
-    */
-    if (m_prev_runtime_ctx && IS_EXCEPTION_CONDITION(sqlstate) &&
-        level == MYSQL_ERROR::WARN_LEVEL_ERROR)
-      return m_prev_runtime_ctx->find_handler(thd,
-                                              sql_errno,
-                                              sqlstate,
-                                              level,
-                                              msg,
-                                              cond_hdl);
-    *cond_hdl= NULL;
-    return FALSE;
-  }
-
-  m_hfound= found;
 
-  MYSQL_ERROR *raised= NULL;
-  DBUG_ASSERT(m_hfound >= 0);
-  DBUG_ASSERT((uint) m_hfound < m_root_parsing_ctx->max_handler_index());
-  raised= & m_raised_conditions[m_hfound];
-  raised->clear();
-  raised->set(sql_errno, sqlstate, level, msg);
-
-  *cond_hdl= raised;
-  return TRUE;
-}
-
-/*
-   Handle the error for a given errno.
-   The severity of the error is adjusted depending of the current sql_mode.
-   If an handler is present for the error (see find_handler()),
-   this function will return true.
-   If a handler is found and if the severity of the error indicate
-   that the current instruction executed should abort,
-   the flag thd->net.report_error is also set.
-   This will cause the execution of the current instruction in a
-   sp_instr* to fail, and give control to the handler code itself
-   in the sp_head::execute() loop.
-
-  SYNOPSIS
-    sql_errno     The error code
-    level         Warning level
-    thd           The current thread
+  if (m_hfound >= 0)
+  {
+    DBUG_ASSERT((uint) m_hfound < m_root_parsing_ctx->max_handler_index());
 
-  RETURN
-    TRUE       if a handler was found.
-    FALSE      if no handler was found.
-*/
-bool
-sp_rcontext::handle_condition(THD *thd,
-                              uint sql_errno,
-                              const char* sqlstate,
-                              MYSQL_ERROR::enum_warning_level level,
-                              const char* msg,
-                              MYSQL_ERROR ** cond_hdl)
-{
-  MYSQL_ERROR::enum_warning_level elevated_level= level;
+    m_raised_conditions[m_hfound].clear();
+    m_raised_conditions[m_hfound].set(sql_errno, sqlstate, level, msg);
 
+    return TRUE;
+  }
 
-  /* Depending on the sql_mode of execution,
-     warnings may be considered errors */
-  if ((level == MYSQL_ERROR::WARN_LEVEL_WARN) &&
-      thd->really_abort_on_warning())
+  /*
+    Only "exception conditions" are propagated to handlers in calling
+    contexts. If no handler is found locally for a "completion condition"
+    (warning or "not found") we will simply resume execution.
+  */
+  if (m_prev_runtime_ctx && IS_EXCEPTION_CONDITION(sqlstate) &&
+      level == MYSQL_ERROR::WARN_LEVEL_ERROR)
   {
-    elevated_level= MYSQL_ERROR::WARN_LEVEL_ERROR;
+    return m_prev_runtime_ctx->find_handler(thd, sql_errno, sqlstate,
+                                            level, msg);
   }
 
-  return find_handler(thd, sql_errno, sqlstate, elevated_level, msg, cond_hdl);
+  return FALSE;
 }
 
 void
@@ -384,7 +337,9 @@ sp_rcontext::pop_handlers(uint count)
 {
   DBUG_ENTER("sp_rcontext::pop_handlers");
   DBUG_ASSERT(m_hcount >= count);
+
   m_hcount-= count;
+
   DBUG_PRINT("info", ("m_hcount: %d", m_hcount));
   DBUG_VOID_RETURN;
 }
@@ -394,7 +349,9 @@ sp_rcontext::push_hstack(uint h)
 {
   DBUG_ENTER("sp_rcontext::push_hstack");
   DBUG_ASSERT(m_hsp < m_root_parsing_ctx->max_handler_index());
+
   m_hstack[m_hsp++]= h;
+
   DBUG_PRINT("info", ("m_hsp: %d", m_hsp));
   DBUG_VOID_RETURN;
 }
@@ -405,21 +362,74 @@ sp_rcontext::pop_hstack()
   uint handler;
   DBUG_ENTER("sp_rcontext::pop_hstack");
   DBUG_ASSERT(m_hsp);
+
   handler= m_hstack[--m_hsp];
+
   DBUG_PRINT("info", ("m_hsp: %d", m_hsp));
   DBUG_RETURN(handler);
 }
 
-void
-sp_rcontext::enter_handler(uint hip, uint hindex)
+/**
+  Prepare found handler to be executed.
+
+  @retval TRUE if an SQL handler is activated (was found) and IP of the
+          first handler instruction.
+  @retval FALSE if there is no active handler
+*/
+
+bool
+sp_rcontext::activate_handler(THD *thd,
+                              uint *ip,
+                              sp_instr *instr,
+                              Query_arena *execute_arena,
+                              Query_arena *backup_arena)
 {
-  DBUG_ENTER("sp_rcontext::enter_handler");
-  DBUG_ASSERT(m_ihsp < m_root_parsing_ctx->max_handler_index());
-  m_in_handler[m_ihsp].ip= hip;
-  m_in_handler[m_ihsp].index= hindex;
-  m_ihsp++;
-  DBUG_PRINT("info", ("m_ihsp: %d", m_ihsp));
-  DBUG_VOID_RETURN;
+  if (m_hfound < 0)
+    return FALSE;
+
+  switch (m_handler[m_hfound].type) {
+  case SP_HANDLER_NONE:
+    break;
+
+  case SP_HANDLER_CONTINUE:
+    thd->restore_active_arena(execute_arena, backup_arena);
+    thd->set_n_backup_active_arena(execute_arena, backup_arena);
+    push_hstack(instr->get_cont_dest());
+
+    /* Fall through */
+
+  default:
+    /* End aborted result set. */
+
+    if (end_partial_result_set)
+      thd->protocol->end_partial_result_set(thd);
+
+    /* Enter handler. */
+
+    DBUG_ASSERT(m_ihsp < m_root_parsing_ctx->max_handler_index());
+    DBUG_ASSERT(m_hfound >= 0);
+
+    m_in_handler[m_ihsp].ip= m_handler[m_hfound].handler;
+    m_in_handler[m_ihsp].index= m_hfound;
+    m_ihsp++;
+
+    DBUG_PRINT("info", ("Entering handler..."));
+    DBUG_PRINT("info", ("m_ihsp: %d", m_ihsp));
+
+    /* Reset error state. */
+
+    thd->clear_error();
+    thd->killed= THD::NOT_KILLED; // Some errors set thd->killed
+                                  // (e.g. "bad data").
+
+    /* Return IP of the activated SQL handler. */
+    *ip= m_handler[m_hfound].handler;
+
+    /* Reset found handler. */
+    m_hfound= -1;
+  }
+
+  return TRUE;
 }
 
 void
@@ -427,9 +437,11 @@ sp_rcontext::exit_handler()
 {
   DBUG_ENTER("sp_rcontext::exit_handler");
   DBUG_ASSERT(m_ihsp);
+
   uint hindex= m_in_handler[m_ihsp-1].index;
   m_raised_conditions[hindex].clear();
   m_ihsp-= 1;
+
   DBUG_PRINT("info", ("m_ihsp: %d", m_ihsp));
   DBUG_VOID_RETURN;
 }
@@ -567,6 +579,11 @@ sp_cursor::fetch(THD *thd, List<struct sp_variable> *vars)
     return -1;
   }
 
+  DBUG_EXECUTE_IF("bug23032_emit_warning",
+                  push_warning(thd, MYSQL_ERROR::WARN_LEVEL_WARN,
+                               ER_UNKNOWN_ERROR,
+                               ER(ER_UNKNOWN_ERROR)););
+
   result.set_spvar_list(vars);
 
   /* Attempt to fetch one row */
diff --git a/sql/sp_rcontext.h b/sql/sp_rcontext.h
index fad253706cb..1af758ed0af 100644
--- a/sql/sp_rcontext.h
+++ b/sql/sp_rcontext.h
@@ -131,67 +131,40 @@ class sp_rcontext : public Sql_alloc
     return m_return_value_set;
   }
 
+  /*
+    SQL handlers support.
+  */
+
   void push_handler(struct sp_cond_type *cond, uint h, int type);
 
   void pop_handlers(uint count);
 
-  // Returns 1 if a handler was found, 0 otherwise.
   bool
   find_handler(THD *thd,
                uint sql_errno,
-               const char* sqlstate,
+               const char *sqlstate,
                MYSQL_ERROR::enum_warning_level level,
-               const char* msg,
-               MYSQL_ERROR ** cond_hdl);
+               const char *msg);
 
-  // If there is an error handler for this error, handle it and return TRUE.
-  bool
-  handle_condition(THD *thd,
-                   uint sql_errno,
-                   const char* sqlstate,
-                   MYSQL_ERROR::enum_warning_level level,
-                   const char* msg,
-                   MYSQL_ERROR ** cond_hdl);
-
-  // Returns handler type and sets *ip to location if one was found
-  inline int
-  found_handler(uint *ip, uint *index)
-  {
-    if (m_hfound < 0)
-      return SP_HANDLER_NONE;
-    *ip= m_handler[m_hfound].handler;
-    *index= m_hfound;
-    return m_handler[m_hfound].type;
-  }
-
-  MYSQL_ERROR* raised_condition() const;
-
-  // Returns true if we found a handler in this context
-  inline bool
-  found_handler_here()
-  {
-    return (m_hfound >= 0);
-  }
+  MYSQL_ERROR *
+  raised_condition() const;
 
-  // Clears the handler find state
-  inline void
-  clear_handler()
-  {
-    m_hfound= -1;
-  }
+  void
+  push_hstack(uint h);
 
-  void push_hstack(uint h);
+  uint
+  pop_hstack();
 
-  uint pop_hstack();
+  bool
+  activate_handler(THD *thd,
+                   uint *ip,
+                   sp_instr *instr,
+                   Query_arena *execute_arena,
+                   Query_arena *backup_arena);
 
-  /**
-    Enter a SQL exception handler.
-    @param hip the handler instruction pointer
-    @param index the handler index
-  */
-  void enter_handler(uint hip, uint index);
 
-  void exit_handler();
+  void
+  exit_handler();
 
   void
   push_cursor(sp_lex_keeper *lex_keeper, sp_instr_cpush *i);
@@ -199,7 +172,7 @@ class sp_rcontext : public Sql_alloc
   void
   pop_cursors(uint count);
 
-  void
+  inline void
   pop_all_cursors()
   {
     pop_cursors(m_ccount);
diff --git a/sql/sql_class.cc b/sql/sql_class.cc
index 7eb4911c744..60a871e9e88 100644
--- a/sql/sql_class.cc
+++ b/sql/sql_class.cc
@@ -845,35 +845,6 @@ MYSQL_ERROR* THD::raise_condition(uint sql_errno,
     }
   }
 
-  /*
-    If a continue handler is found, the error message will be cleared
-    by the stored procedures code.
-  */
-  if (!is_fatal_error && spcont &&
-      spcont->handle_condition(this, sql_errno, sqlstate, level, msg, &cond))
-  {
-    /*
-      Do not push any warnings, a handled error must be completely
-      silenced.
-    */
-    DBUG_RETURN(cond);
-  }
-
-  /* Un-handled conditions */
-
-  cond= raise_condition_no_handler(sql_errno, sqlstate, level, msg);
-  DBUG_RETURN(cond);
-}
-
-MYSQL_ERROR*
-THD::raise_condition_no_handler(uint sql_errno,
-                                const char* sqlstate,
-                                MYSQL_ERROR::enum_warning_level level,
-                                const char* msg)
-{
-  MYSQL_ERROR *cond= NULL;
-  DBUG_ENTER("THD::raise_condition_no_handler");
-
   query_cache_abort(&query_cache_tls);
 
   /* FIXME: broken special case */
@@ -886,6 +857,7 @@ THD::raise_condition_no_handler(uint sql_errno,
   cond= warning_info->push_warning(this, sql_errno, sqlstate, level, msg);
   DBUG_RETURN(cond);
 }
+
 extern "C"
 void *thd_alloc(MYSQL_THD thd, unsigned int size)
 {
diff --git a/sql/sql_class.h b/sql/sql_class.h
index c719f5a09ad..b23b65dae2f 100644
--- a/sql/sql_class.h
+++ b/sql/sql_class.h
@@ -2800,23 +2800,6 @@ private:
                   MYSQL_ERROR::enum_warning_level level,
                   const char* msg);
 
-  /**
-    Raise a generic SQL condition, without activation any SQL condition
-    handlers.
-    This method is necessary to support the RESIGNAL statement,
-    which is allowed to bypass SQL exception handlers.
-    @param sql_errno the condition error number
-    @param sqlstate the condition SQLSTATE
-    @param level the condition level
-    @param msg the condition message text
-    @return The condition raised, or NULL
-  */
-  MYSQL_ERROR*
-  raise_condition_no_handler(uint sql_errno,
-                             const char* sqlstate,
-                             MYSQL_ERROR::enum_warning_level level,
-                             const char* msg);
-
 public:
   /** Overloaded to guard query/query_length fields */
   virtual void set_statement(Statement *stmt);
diff --git a/sql/sql_error.cc b/sql/sql_error.cc
index e5d0f79b2d7..8c038e10a1f 100644
--- a/sql/sql_error.cc
+++ b/sql/sql_error.cc
@@ -494,14 +494,6 @@ void Warning_info::clear_warning_info(ulonglong warn_id_arg)
   m_current_row_for_warning= 1; /* Start counting from the first row */
 }
 
-void Warning_info::reserve_space(THD *thd, uint count)
-{
-  /* Make room for count conditions */
-  while ((m_warn_list.elements > 0) &&
-        ((m_warn_list.elements + count) > thd->variables.max_error_count))
-    m_warn_list.pop();
-}
-
 /**
   Append warnings only if the original contents of the routine
   warning info was replaced.
diff --git a/sql/sql_error.h b/sql/sql_error.h
index 9e649a004df..87e98e27673 100644
--- a/sql/sql_error.h
+++ b/sql/sql_error.h
@@ -153,8 +153,8 @@ private:
   Representation of a SQL condition.
   A SQL condition can be a completion condition (note, warning),
   or an exception condition (error, not found).
-  @note This class is named MYSQL_ERROR instead of SQL_condition for historical reasons,
-  to facilitate merging code with previous releases.
+  @note This class is named MYSQL_ERROR instead of SQL_condition for
+  historical reasons, to facilitate merging code with previous releases.
 */
 class MYSQL_ERROR : public Sql_alloc
 {
@@ -471,18 +471,6 @@ public:
 
   ulong statement_warn_count() const { return m_statement_warn_count; }
 
-  /**
-    Reserve some space in the condition area.
-    This is a privileged operation, reserved for the RESIGNAL implementation,
-    as only the RESIGNAL statement is allowed to remove conditions from
-    the condition area.
-    For other statements, new conditions are not added to the condition
-    area once the condition area is full.
-    @param thd The current thread
-    @param count The number of slots to reserve
-  */
-  void reserve_space(THD *thd, uint count);
-
   /** Add a new condition to the current list. */
   MYSQL_ERROR *push_warning(THD *thd,
                             uint sql_errno, const char* sqlstate,
diff --git a/sql/sql_signal.cc b/sql/sql_signal.cc
index f340da373e8..09e9a828fa1 100644
--- a/sql/sql_signal.cc
+++ b/sql/sql_signal.cc
@@ -499,18 +499,6 @@ bool Resignal_statement::execute(THD *thd)
   }
 
   /* RESIGNAL with signal_value */
-
-  /* Make room for 2 conditions */
-  thd->warning_info->reserve_space(thd, 2);
-
-  MYSQL_ERROR *raised= NULL;
-  raised= thd->raise_condition_no_handler(signaled->get_sql_errno(),
-                                          signaled->get_sqlstate(),
-                                          signaled->get_level(),
-                                          signaled->get_message_text());
-  if (raised)
-    raised->copy_opt_attributes(signaled);
-
   result= raise_condition(thd, signaled);
 
   DBUG_RETURN(result);