Ignored width extension for constant ?: condition

OPEN: last verified in Quartus 17.0

Consider the following test case:

module issue_044(a, y);
  input [3:0] a;
  output [3:0] y;
  assign y = &(0 ? 0 : (&a));

Because of the rules for verilog bit width extension, y in this module is constant zero: When a=4'b1111, then &a=1'b1, which is extended to the size of '0' (which must be at least 32 bits), yielding &(32'b000...0001) which evaluates to zero. For all other values of a the example is trivially zero.

But Quartus 15.0 incorrectly converts the expression to &a.

Crosscheck: Vivado 2015.1, XSim 2015.1, Modelsim 10.3d, Icarus Verilog (git 02ee387), and Verilator (git e5af46d) all agree on the correct behavior.

2015-05-15 Reported via Altera mySupport (SR #11146970)
2017-07-01 Still broken in Quartus II 17.0

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