The following module should set y to constant 6'b110011, but instead it just hangs quartus 13.1:
module issue_021(y); output [5:0] y; assign y = 6'd3 ** 123456789; endmodule
Quartus seems to try to evaluate this expression by performing 123456789 multiplications instead of using a proper power-modulus algorithm.
In my tests I have synthesized the module with
quartus_map issue_021 --source=issue_021.v --family="Cyclone III"
Crosscheck: Modelsim 10.1d can simulate this module in an instant and Vivado 2013.4 can synthesize it correctly.
2014-01-25 Reported via Altera mySupport (SR #11025546)
2014-01-27 Bugfix for Quartus II v14.1 prospected by Altera Support
2014-09-28 Verified that bug is still present in Quartus II v14.0
2015-05-15 Still broken in Quartus II 15.0
2017-07-01 Still broken in Quartus II 17.0