In reply to mohabhat:
For multiclocking you can only use ##0 or ##1 to switch the clocks.
Thus, this is illegal
@(posedge clk0) x ##2 @(posedge clk1) y;
(9) - EDA Playground // is OK
property diff_clocks_prop ;
@(posedge clk0) x ##1 @(posedge clk1) y; // line 15
endproperty
assert property ( diff_clocks_prop );
Ben