Bug in XSIM when combining reduce op and $signed/$unsigned

CLOSED: fixed in XSim 2015.1

The following module should return 3'b001:

module issue_017(y);
  output [2:0] y;
  assign y = &($signed(2'b11));
  initial #10 $display("%b", y);

But xsim 2013.4 returns 3'b000 instead.

I get the the same bug when I replace $signed with $unsigned. The bug goes away if I do not use $signed or $unsigned or reduce the size of y. Somehow the size of y "leaks through" to the self-determined operand of the & reduce operator when used with $signed or $unsigned.

In my tests I have run this module with:

xvlog issue_017.v
xelab -R work.issue_017

Crosscheck: Vivado 2013.4, XST 14.7, Quartus 13.1 and Modelsim 10.1d implement this correctly.

2014-01-25 Reported bug in Xilinx Support Forum
2014-04-16 Still broken in XSim 2014.1
2015-05-15 Fixed in XSim 2015.1

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