SC_CTOR initialization error ???

[rayzekus]

I am a novice at SystemC (some OOP background but not much) ...

I am getting an error for the code below ... ../src/xor2.h:20:31: error: invalid initializer for array member 'nand<2> xor2::nand2 [4]'

I have much more complicated but netted my problem down to this much simpler and smaller example ...

#include "systemc.h"

template <int width>
SC_MODULE(nand) {
    sc_in<bool> A[width];
    sc_out<bool> F;

    void nand_func() {
        F.write(!and_reduce(A));
    }

    SC_CTOR(nand) {
        SC_METHOD(nand_func);
        sensitive << A;
    }
};

#include "systemc.h"

#include "nand.h"

SC_MODULE(xor2) {
    sc_in<bool> A, B;
    sc_out<bool> F;

    nand<2> nand2[4];

    sc_signal<bool> sig1, sig2, sig3;

    SC_CTOR(xor2) : nand2("NAND2") {
        nand2[0].A[0](A);
        nand2[0].A[1](B);
        nand2[0].F(sig1);

        nand2[1].A[0](A);
        nand2[1].A[1](sig1);
        nand2[1].F(sig2);

        nand2[2].A[0](sig1);
        nand2[2].A[1](B);
        nand2[2].F(sig3);

        nand2[3].A[0](sig2);
        nand2[3].A[1](sig3);
        nand2[3].F(F);
    }
};

I would greatly appreciate any help and suggestions of ways to use multiple template'd modules in this way ...

 

xor2.h

nand.h

[ralph.goergen]

Hi.

You cannot do an array or a std::vector of SystemC modules. Both would require a default constructor which is not available for sc_modules.

Use sc_vector instead. See Section 8.5 in the SystemC LRM (IEEE 1666:2011).

Regards

Ralph

[rayzekus]

Thanks Ralph,

I tried what you suggested and that should be the right answer but I get the following error ...

../src/xor2.h:17:38: warning: non-static data member initializers only available with -std=c++11 or -std=gnu++11
  sc_vector<nand<2> > nand2{"NAND2", 4};
                                      ^

As I said I am a novice at this ... and my next Q isn't SystemC but maybe you can help me ...

I am using Eclipse and Cygwin gcc ... Can I add the c++11option to fix the error I got?

[David Black]

Assumes you are using a version of c++ that supports c++11, just add -std=c++11 to fix this problem or move the constructor arguments to the initializer list of your constructor, which will require abandoning the SC_CTOR macro in favor of full C++ constructor syntax. Or you  use the deferred vector construction.

Gcc 4.8 or newer supports c++11 if I recall correctly.

[rayzekus]

Thanks David,

Looks like Cygwin gcc supports c++11 ... I used sc_vector compiles cleanly :-)