title: Vivado Error named: [Synth 8-6859] multi-driven net on pin
body: <pre><code>module top(  
  input [59:0] first,   
  input [59:0] second,   
  output out
          ); 
  
  wire [14:0] out_wire;
  
  assign first[19:0]= 20'b1111111111111111111;  
  assign first[39:20]= 20'b0000000000000000000;  
  assign first[59:40]=20'b11001100110011001100;
  
   .....
   ... 
   ..
  </code></pre>
  
  <p>I am getting the error in the title when synthesizing if I include the <code>assign</code> statements. How do I initialize these 3 assignment values to first[59:0] properly? </p>
  
  <p>The whole design is combinational.</p>