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AR# 22098

8.2i XST-"ERROR:HDLParsers:818 - Cannot determine the type of the selector &"


When I run my design in XST, the following error occurs:

"ERROR:HDLParsers:818 - Can not determine the type of the selector &"

The following example results in the error:

signal a,b : std_logic;

case (a & b) is

end case;


This error occurs when you concatenate two signals in the case condition. To work around this issue, create an intermediate signal for the concatenation.

For example:

signal a,b : std_logic;

signal concat : std_logic_vector (1 downto 0);

concat <= a & b ;

case (concat ) is

end case;

A fix is currently not scheduled for this issue.

AR# 22098
Date Created 09/04/2007
Last Updated 12/15/2012
Status Active
Type General Article