Strange Verific bug with replicate and xor-reduce

CLOSED: fixed in Verific 482_32_150519

The expression in this module is constant zero: Whatever the inner expression evaluates to, the replication operator duplicates it, thus only yielding an even number of set bits. The XOR-reduce is only true if the number of set bits in the operand is odd.

module issue_056(a, y);
  input [3:0] a;
  output [3:0] y;

  assign y = ^{2{{|1, |1 << a}}};

But Verific 463_32_140722 thinks that for example a=0 yields y=1.

2014-07-25 Reported bug to Verific support
2014-07-26 Bug added to issue tracker: VIPER Issue #8862
2015-05-20 Fixed in Verific 482_32_150519

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