*** pgsql/src/backend/commands/functioncmds.c	2009/02/24 01:38:09	1.108
--- pgsql/src/backend/commands/functioncmds.c	2009/03/04 11:53:53	1.109
***************
*** 10,16 ****
   *
   *
   * IDENTIFICATION
!  *	  $PostgreSQL: pgsql/src/backend/commands/functioncmds.c,v 1.107 2009/01/06 02:01:27 tgl Exp $
   *
   * DESCRIPTION
   *	  These routines take the parse tree and pick out the
--- 10,16 ----
   *
   *
   * IDENTIFICATION
!  *	  $PostgreSQL: pgsql/src/backend/commands/functioncmds.c,v 1.108 2009/02/24 01:38:09 tgl Exp $
   *
   * DESCRIPTION
   *	  These routines take the parse tree and pick out the
*************** CreateCast(CreateCastStmt *stmt)
*** 1470,1475 ****
--- 1470,1477 ----
  {
  	Oid			sourcetypeid;
  	Oid			targettypeid;
+ 	char		sourcetyptype;
+ 	char		targettyptype;
  	Oid			funcid;
  	int			nargs;
  	char		castcontext;
*************** CreateCast(CreateCastStmt *stmt)
*** 1483,1497 ****
  
  	sourcetypeid = typenameTypeId(NULL, stmt->sourcetype, NULL);
  	targettypeid = typenameTypeId(NULL, stmt->targettype, NULL);
  
  	/* No pseudo-types allowed */
! 	if (get_typtype(sourcetypeid) == TYPTYPE_PSEUDO)
  		ereport(ERROR,
  				(errcode(ERRCODE_WRONG_OBJECT_TYPE),
  				 errmsg("source data type %s is a pseudo-type",
  						TypeNameToString(stmt->sourcetype))));
  
! 	if (get_typtype(targettypeid) == TYPTYPE_PSEUDO)
  		ereport(ERROR,
  				(errcode(ERRCODE_WRONG_OBJECT_TYPE),
  				 errmsg("target data type %s is a pseudo-type",
--- 1485,1501 ----
  
  	sourcetypeid = typenameTypeId(NULL, stmt->sourcetype, NULL);
  	targettypeid = typenameTypeId(NULL, stmt->targettype, NULL);
+ 	sourcetyptype = get_typtype(sourcetypeid);
+ 	targettyptype = get_typtype(targettypeid);
  
  	/* No pseudo-types allowed */
! 	if (sourcetyptype == TYPTYPE_PSEUDO)
  		ereport(ERROR,
  				(errcode(ERRCODE_WRONG_OBJECT_TYPE),
  				 errmsg("source data type %s is a pseudo-type",
  						TypeNameToString(stmt->sourcetype))));
  
! 	if (targettyptype == TYPTYPE_PSEUDO)
  		ereport(ERROR,
  				(errcode(ERRCODE_WRONG_OBJECT_TYPE),
  				 errmsg("target data type %s is a pseudo-type",
*************** CreateCast(CreateCastStmt *stmt)
*** 1615,1620 ****
--- 1619,1651 ----
  			ereport(ERROR,
  					(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
  					 errmsg("source and target data types are not physically compatible")));
+ 
+ 		/*
+ 		 * We know that composite, enum and array types are never binary-
+ 		 * compatible with each other.  They all have OIDs embedded in them.
+ 		 *
+ 		 * Theoretically you could build a user-defined base type that is
+ 		 * binary-compatible with a composite, enum, or array type.  But we
+ 		 * disallow that too, as in practice such a cast is surely a mistake.
+ 		 * You can always work around that by writing a cast function.
+ 		 */
+ 		if (sourcetyptype == TYPTYPE_COMPOSITE ||
+ 			targettyptype == TYPTYPE_COMPOSITE)
+ 			ereport(ERROR,
+ 					(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
+ 					 errmsg("composite data types are not binary-compatible")));
+ 
+ 		if (sourcetyptype == TYPTYPE_ENUM ||
+ 			targettyptype == TYPTYPE_ENUM)
+ 			ereport(ERROR,
+ 					(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
+ 					 errmsg("enum data types are not binary-compatible")));
+ 
+ 		if (OidIsValid(get_element_type(sourcetypeid)) ||
+ 			OidIsValid(get_element_type(targettypeid)))
+ 			ereport(ERROR,
+ 					(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
+ 					 errmsg("array data types are not binary-compatible")));
  	}
  
  	/*