Fixed BUG#14376: MySQL crash on scoped variable (re)initialization

  Added finer scope control for default clauses of local variable
  declarations.


mysql-test/r/sp.result:
  New test case for BUG#14376.
mysql-test/t/sp.test:
  New test case for BUG#14376.
sql/sp_pcontext.cc:
  Added boundary variable for local parameters/variables,
  for better scope control of default values.
sql/sp_pcontext.h:
  Added boundary variable for local parameters/variables,
  for better scope control of default values.
sql/sql_yacc.yy:
  Make the variables of the current DECLARE "invisible" to its DEFAULT clause.

1 files changed, 16 insertions, 0 deletions

diff --git a/sql/sp_pcontext.h b/sql/sp_pcontext.h
index bd2259cb6fb..fbeac37c058 100644
--- a/sql/sp_pcontext.h
+++ b/sql/sp_pcontext.h
@@ -164,6 +164,7 @@ class sp_pcontext : public Sql_alloc
   {
     while (num--)
       pop_dynamic(&m_pvar);
+    m_pboundary= m_pvar.elements;
   }
 
   // Find by name
@@ -183,6 +184,14 @@ class sp_pcontext : public Sql_alloc
     return p;
   }
 
+  // Set the current scope boundary (for default values)
+  // The argument is the number of variables to skip.
+  inline void
+  declare_var_boundary(uint n)
+  {
+    m_pboundary= m_pvar.elements-n;
+  }
+
   //
   // Labels
   //
@@ -287,6 +296,13 @@ private:
 
   uint m_poffset;		// Variable offset for this context
   uint m_coffset;		// Cursor offset for this context
+  /*
+    Boundary for finding variables in this in this context.
+    This is normally the same as m_pvar.elements, but differs during
+    parsing of DECLARE ... DEFAULT, to get the scope right for DEFAULT
+    values.
+  */
+  uint m_pboundary;
 
   DYNAMIC_ARRAY m_pvar;		// Parameters/variables
   DYNAMIC_ARRAY m_cond;		// Conditions