ModelSim-Altera show error on compilation while Quartus not.

Altera_Forum · ‎07-12-2018

Quartus compile this code without any errors.

code.sv

`timescale 1 ns/ 1 nsmodule test013_LITERAL (
    input  A,
    input  B,
    output C
);
    struct{enum{IDLE,
                SOME_STAGE_1} FSM;
             logic some_register;
            } first_machine;
    struct{enum{IDLE,
                SOME_STAGE_2} FSM;
             logic some_register;
            } second_machine;            
    assign C = A ^ B;    
endmodule

testbench.vt

`timescale 1 ns/ 1 nsmodule testbench();
    reg test_A;
    reg test_B;
    wire test_C;
    test013_LITERAL DUT (.A(test_A),
                         .B(test_B),
                         .C(test_C));
    initial begin    
       # 100
            test_A = 0;
            test_B = 0;
       # 100
            test_A = 1;
            test_B = 0;    
       # 100
            test_A = 0;
            test_B = 1;        
       # 100
            test_A = 1;
            test_B = 1;    
    end    
endmodule

But modelsim-Altera show error: "enum literal name 'idle' already exists."

Emm... Syntaxis of SV allowed me to use enum in struct but literal scope in struct is still common while registers scope in struct is privat.

Can I write on SystemVerilog two structs in one module and then make enum in each struct with same literal ("IDLE" for example)? Is another struct means another scope?

If not can anyone describe what structs are used for?

If yes can anyone describe to me how to win ModelSim-Altera?

Altera_Forum · ‎07-18-2018

Hi,

--- Quote Start ---

Can I write on SystemVerilog two structs in one module and then make enum in each struct with the same literal ("IDLE" for example)? Is another struct means another scope?

If not can anyone describe what structs are used for?

If yes can anyone describe to me how to win ModelSim-Altera?

--- Quote End ---

You can use two structs in one module but you can`t use the same enumeration constants between two different enumeration types (since two structs have individual scope) inside two different structs.

No two enum types can use the same enumeration constants between them

If you want to use the same enumeration constants between two different enumeration types, you'll have to create unique prefixes or suffixes for them (for example IDLE_1)

Best Regards

Vikas Jathar

(This message was posted on behalf of Intel Corporation)