interface 多驱动错误

payne_shu

module test_top;
     test_if    u1_test_if();
     test_int  u_test_int();

     assign u1_test_if.u_test_if1.abc=1'b0;
endmodule

module test_int;
    test_if u2_test_if();
    assign u2_test_if.u_test_if1.abc=1'b1;
endmodule

interface test_if();
   test_if1 u_test_if1();
endinterface

interface test_if1();
   logic abc;
endinterface

编译上面的代码后报错：
Error-[ICSD] Combination of structural drivers
test_top.sv, 18
Invalid combination of structural drivers
Variable "abc" is driven by multiple structural drivers.
"test_top.sv", 18: logic abc;
"test_top.sv", 5: assign u1_test_if.u_test_if1.abc=1'b0;
"test_top.sv", 10: assign u2_test_if.u_test_if1.abc=1'b1;

求解~~~

payne_shu

如果test_if不再包test_if1，就没有问题，如下：
module test_top;
     test_if    u1_test_if();
     test_int  u_test_int();

     assign u1_test_if.abc=1'b0;
endmodule

module test_int;
    test_if u2_test_if();
    assign u2_test_if.abc=1'b1;
endmodule

interface test_if();
   //test_if1 u_test_if1();
    logic abc;
endinterface