Xilinx ISE Ceil and Floor Can't Synthesize But Can Simulate?

[hal9001]

Im using Xilinx ISE 14.7 for Spartan 3A project. I want to use $ceil and $floor to calculate parameters in my verilog file.
Test bench simulates without error.
Synthesize gives this error

Code: [Select]

ERROR:HDLCompilers:26 - unexpected token: '$ceil'
ERROR:HDLCompilers:26 - expecting ';', found ')'
ERROR:HDLCompilers:26 - unexpected token: '$floor'
ERROR:HDLCompilers:26 - expecting ';', found ')'
The code is

Code: [Select]

parameter NUMBER = 2.5;
parameter integer CEIL_NUMBER= $ceil(NUMBER );
parameter integer FLOOR_NUMBER= $floor(NUMBER );
Is there a work around?


Cheers