Fixed the broken backpatching implementation.

Implemented IF-THEN-ELSE.


sql/sp_head.cc:
  Reimplemented the broken backpatching, so it works for nested constructions and
  IF-THEN-ELSE too.
sql/sp_head.h:
  Reimplemented the broken backpatching, so it works for nested constructions and
  IF-THEN-ELSE too.
sql/sp_pcontext.cc:
  Return the value from push-methods, for convenience.
sql/sp_pcontext.h:
  Return the value from push-methods, for convenience.
sql/sql_yacc.yy:
  Implemented IF-THEN-ELSE.
  Corrected for the new backpatch method.

1 files changed, 5 insertions, 5 deletions

diff --git a/sql/sp_pcontext.h b/sql/sp_pcontext.h
index 7c8e2ba0c43..2eb59172365 100644
--- a/sql/sp_pcontext.h
+++ b/sql/sp_pcontext.h
@@ -38,7 +38,7 @@ typedef struct
   my_bool isset;
 } sp_pvar_t;
 
-typedef struct
+typedef struct sp_label
 {
   char *name;
   uint ip;			// Instruction index
@@ -116,10 +116,10 @@ class sp_pcontext : public Sql_alloc
     return m_pvar+i;
   }
 
-  void
+  sp_label_t *
   push_label(char *name, uint ip);
 
-  void
+  sp_label_t *
   push_gen_label(uint ip);
 
   sp_label_t *
@@ -131,10 +131,10 @@ class sp_pcontext : public Sql_alloc
     return m_label.head();
   }
 
-  inline void
+  inline sp_label_t *
   pop_label()
   {
-    m_label.pop();
+    return m_label.pop();
   }
 
 private: