Xilinx ISE, expression not globally static inside generic map

[Zo Ki]

Hello,

Is this allowed inside Xilinx ISE : generic map (record1.field1'length) ??

Previously I have defined record:

type test_record is record
field1 : std_logic_vector(31 downto 0);
field2 : std_logic_vector(31 downto 0);
end record;

constant record1 : test_record := ((others => '0'),(others => '0'));

I get this error message:

The actual value (Attribute name) associated with a generic must be a globally static expression

Thanks in advance