Fixed BUG#13133: Local variables in stored procedures are not initialized correctly.

  Have to init. all local variables in their frames, not just once at the beginning
  of invocation.

mysql-test/r/sp.result

@@ -3225,4 +3225,43 @@ select @var|
 @var
 abcdabcd
 drop procedure bug12849_2|
+drop procedure if exists bug131333|
+drop function if exists bug131333|
+create procedure bug131333()
+begin
+begin
+declare a int;
+select a;
+set a = 1;
+select a;
+end;
+begin
+declare b int;
+select b;
+end;
+end|
+create function bug131333()
+returns int
+begin
+begin
+declare a int;
+set a = 1;
+end;
+begin
+declare b int;
+return b;
+end;
+end|
+call bug131333()|
+a
+NULL
+a
+1
+b
+NULL
+select bug131333()|
+bug131333()
+NULL
+drop procedure bug131333|
+drop function bug131333|
 drop table t1,t2;

mysql-test/t/sp.test

@@ -4063,6 +4063,51 @@ call bug12849_2(@var)|
 select @var|
 drop procedure bug12849_2|
 
+#
+# BUG#13133: Local variables in stored procedures are not initialized correctly.
+#
+--disable_warnings
+drop procedure if exists bug131333|
+drop function if exists bug131333|
+--enable_warnings
+create procedure bug131333()
+begin
+  begin
+    declare a int;
+
+    select a;
+    set a = 1;
+    select a;
+  end;
+  begin
+    declare b int;
+
+    select b;
+  end;
+end|
+
+create function bug131333()
+  returns int
+begin
+  begin
+    declare a int;
+
+    set a = 1;
+  end;
+  begin
+    declare b int;
+
+    return b;
+  end;
+end|
+
+call bug131333()|
+select bug131333()|
+
+drop procedure bug131333|
+drop function bug131333|
+
+
 #
 # BUG#NNNN: New bug synopsis
 #

sql/sp_head.cc

@@ -1078,7 +1078,6 @@ sp_head::execute_function(THD *thd, Item **argp, uint argcount, Item **resp)
   sp_rcontext *octx = thd->spcont;
   sp_rcontext *nctx = NULL;
   uint i;
-  Item_null *nit;
   int ret= -1;                                  // Assume error
 
   if (argcount != params)
@@ -1109,22 +1108,15 @@ sp_head::execute_function(THD *thd, Item **argp, uint argcount, Item **resp)
     nctx->push_item(it);
   }
 
+
   /*
     The rest of the frame are local variables which are all IN.
-    Default all variables to null (those with default clauses will
-    be set by an set instruction).
+    Push NULLs to get the right size (and make the reuse mechanism work) -
+    the will be initialized by set instructions in each frame.
   */
-
-  nit= NULL;                       // Re-use this, and only create if needed
   for (; i < csize ; i++)
-  {
-    if (! nit)
-    {
-      if (!(nit= new Item_null()))
-        DBUG_RETURN(-1);
-    }
-    nctx->push_item(nit);
-  }
+    nctx->push_item(NULL);
+
   thd->spcont= nctx;
 
   binlog_save_options= thd->options;
@@ -1321,23 +1313,14 @@ int sp_head::execute_procedure(THD *thd, List<Item> *args)
       close_thread_tables(thd, 0, 0);
 
     DBUG_PRINT("info",(" %.*s: eval args done", m_name.length, m_name.str));
+
     /*
       The rest of the frame are local variables which are all IN.
-      Default all variables to null (those with default clauses will
-      be set by an set instruction).
+      Push NULLs to get the right size (and make the reuse mechanism work) -
+      the will be initialized by set instructions in each frame.
     */
     for (; i < csize ; i++)
-    {
-      if (! nit)
-      {
-	if (!(nit= new Item_null()))
-        {
-          ret= -1;
-          break;
-        }
-      }
-      nctx->push_item(nit);
-    }
+      nctx->push_item(NULL);
   }
 
   thd->spcont= nctx;

sql/sp_pcontext.cc

@@ -184,7 +184,6 @@ sp_pcontext::push_pvar(LEX_STRING *name, enum enum_field_types type,
     p->type= type;
     p->mode= mode;
     p->offset= current_pvars();
-    p->isset= (mode == sp_param_out ? FALSE : TRUE);
     p->dflt= NULL;
     insert_dynamic(&m_pvar, (gptr)&p);
   }

sql/sp_pcontext.h

@@ -35,7 +35,6 @@ typedef struct sp_pvar
   enum enum_field_types type;
   sp_param_mode_t mode;
   uint offset;			// Offset in current frame
-  my_bool isset;
   Item *dflt;
 } sp_pvar_t;
 
@@ -147,15 +146,6 @@ class sp_pcontext : public Sql_alloc
       p->type= type;
   }
 
-  inline void
-  set_isset(uint i, my_bool val)
-  {
-    sp_pvar_t *p= find_pvar(i);
-
-    if (p)
-      p->isset= val;
-  }
-
   inline void
   set_default(uint i, Item *it)
   {

sql/sql_yacc.yy

@@ -1657,42 +1657,41 @@ sp_decls:
 	;
 
 sp_decl:
-	  DECLARE_SYM sp_decl_idents type 
+          DECLARE_SYM sp_decl_idents type 
           { Lex->sphead->reset_lex(YYTHD); }
           sp_opt_default
-	  {
-	    LEX *lex= Lex;
-	    sp_pcontext *ctx= lex->spcont;
-	    uint max= ctx->context_pvars();
-	    enum enum_field_types type= (enum enum_field_types)$3;
-	    Item *it= $5;
+          {
+            LEX *lex= Lex;
+            sp_pcontext *ctx= lex->spcont;
+            uint max= ctx->context_pvars();
+            enum enum_field_types type= (enum enum_field_types)$3;
+            Item *it= $5;
+            bool has_default= (it != NULL);
 
-	    for (uint i = max-$2 ; i < max ; i++)
-	    {
-	      ctx->set_type(i, type);
-	      if (! it)
-	        ctx->set_isset(i, FALSE);
-	      else
-	      {
-	        sp_instr_set *in= new sp_instr_set(lex->sphead->instructions(),
-	                                           ctx,
-						   ctx->pvar_context2index(i),
-                                                   it, type, lex,
-                                                   (i == max - 1));
-
-                /*
-                  The last instruction is assigned to be responsible for
-                  freeing LEX.
-                */
-	        lex->sphead->add_instr(in);
-	        ctx->set_isset(i, TRUE);
-		ctx->set_default(i, it);
-	      }
-	    }
+            for (uint i = max-$2 ; i < max ; i++)
+            {
+              sp_instr_set *in;
+
+              ctx->set_type(i, type);
+              if (! has_default)
+                it= new Item_null();  /* QQ Set to the type with null_value? */
+              in = new sp_instr_set(lex->sphead->instructions(),
+                                    ctx,
+                                    ctx->pvar_context2index(i),
+                                    it, type, lex,
+                                    (i == max - 1));
+
+              /*
+                The last instruction is assigned to be responsible for
+                freeing LEX.
+              */
+              lex->sphead->add_instr(in);
+              ctx->set_default(i, it);
+            }
             lex->sphead->restore_lex(YYTHD);
-	    $$.vars= $2;
-	    $$.conds= $$.hndlrs= $$.curs= 0;
-	  }
+            $$.vars= $2;
+            $$.conds= $$.hndlrs= $$.curs= 0;
+          }
 	| DECLARE_SYM ident CONDITION_SYM FOR_SYM sp_cond
 	  {
 	    LEX *lex= Lex;
@@ -2268,7 +2267,6 @@ sp_fetch_list:
 	      sp_instr_cfetch *i= (sp_instr_cfetch *)sp->last_instruction();
 
 	      i->add_to_varlist(spv);
-	      spv->isset= TRUE;
 	    }
 	  }
 	|
@@ -2290,7 +2288,6 @@ sp_fetch_list:
 	      sp_instr_cfetch *i= (sp_instr_cfetch *)sp->last_instruction();
 
 	      i->add_to_varlist(spv);
-	      spv->isset= TRUE;
 	    }
 	  }
 	;
@@ -5894,7 +5891,6 @@ select_var_ident:
 	     else
 	     {
 	       ((select_dumpvar *)lex->result)->var_list.push_back( new my_var($1,1,t->offset,t->type));
-	       t->isset= TRUE;
 	     }
 	   }
            ;
@@ -7925,7 +7921,6 @@ sys_option_value:
             sp_set= new sp_instr_set(lex->sphead->instructions(), ctx,
                                      spv->offset, it, spv->type, lex, TRUE);
             lex->sphead->add_instr(sp_set);
-            spv->isset= TRUE;
           }
         }
         | option_type TRANSACTION_SYM ISOLATION LEVEL_SYM isolation_types