Fix a couple of places where the plpgsql grammar would produce an unhelpful

'syntax error' message, rather than something that might draw one's
attention to a missing or wrong-type variable declaration.  Per recent
gripe.

src/pl/plpgsql/src/gram.y

@@ -9,7 +9,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/pl/plpgsql/src/gram.y,v 1.114 2008/09/02 20:37:55 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/pl/plpgsql/src/gram.y,v 1.115 2008/09/10 01:09:45 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -741,6 +741,18 @@ getdiag_target	: T_SCALAR
 						check_assignable(yylval.scalar);
 						$$ = yylval.scalar->dno;
 					}
+				| T_ROW
+					{
+						yyerror("expected an integer variable");
+					}
+				| T_RECORD
+					{
+						yyerror("expected an integer variable");
+					}
+				| T_WORD
+					{
+						yyerror("expected an integer variable");
+					}
 				;
 
 
@@ -1669,6 +1681,18 @@ cursor_variable	: T_SCALAR
 						}
 						$$ = (PLpgSQL_var *) yylval.scalar;
 					}
+				| T_ROW
+					{
+						yyerror("expected a cursor or refcursor variable");
+					}
+				| T_RECORD
+					{
+						yyerror("expected a cursor or refcursor variable");
+					}
+				| T_WORD
+					{
+						yyerror("expected a cursor or refcursor variable");
+					}
 				;
 
 exception_sect	: