We have detected your current browser version is not the latest one. Xilinx.com uses the latest web technologies to bring you the best online experience possible. Please upgrade to a Xilinx.com supported browser:Chrome, Firefox, Internet Explorer 11, Safari. Thank you!

AR# 44523

XST - Severity Change for XST message "WARNING:HDLCompiler:1419" beginning in ISE 13.3 Software


The message "WARNING:HDLCompiler:1419" produced by Verific XST prior to 13.3 softwarewill change to "ERROR:HDLCompiler:1419" beginning with version 13.3 of XST for cases where a case statement contains no items.




module top(input sel, d0, d1, output reg out);

always @(*)
1'b0: out = d0;
1'b1: out = d1;



The Verific XST (prior to the version 13.3 software) would have given the following warning message for the above piece of code:

WARNING:HDLCompiler:1419 - "top.v" Line 9: Case statement with no case item violates IEEE 1800 syntax

Beginning with the version 13.3 of XST, this warning is modified to an error without any change to the actual information or message as follows:

ERROR:HDLCompiler:1419 - "top.v" Line 9: Case statement with no case item violates IEEE 1800 syntax

In the above example, because all ofthe case items are commented out from the case statement, it leaves the case statement empty, which violates the IEEE 1800 syntax. Therefore, it is to your benefit to avoid using an empty case statement.

AR# 44523
Date Created 10/14/2011
Last Updated 12/15/2012
Status Active
Type General Article
  • ISE Design Suite - 13.3