// a.d
import b;
void main()
{
	new A();
}

// b.d
class A
{
	protected this(){}

}


When these source codes are compiled with dmd trunk r628, dmd outputs a correct error message and crashes.


>dmd a b
a.d(4): Error: class b.A member this is not accessible
<-- crash!!


The cause of the crash is an access to the null pointer as shown below.


// toctype.c
...
type *TypeFunction::toCtype()
{   type *t;

    if (ctype)
        return ctype;

    if (1)
    {
        param_t *paramtypes;
        tym_t tyf;
        type *tp;

        paramtypes = NULL;
        size_t nparams = Parameter::dim(parameters);
        for (size_t i = 0; i < nparams; i++)
        {   Parameter *arg = Parameter::getNth(parameters, i);
            tp = arg->type->toCtype();
            if (arg->storageClass & (STCout | STCref))
            {   // C doesn't have reference types, so it's really a pointer
                // to the parameter type
                tp = type_allocn(TYref, tp);
            }
            param_append_type(&paramtypes,tp);
        }
        tyf = totym();
        t = type_alloc(tyf);
        t->Tflags |= TFprototype;
        if (varargs != 1)
            t->Tflags |= TFfixed;
        ctype = t;
        t->Tnext = next->toCtype(); // <<<<<<<<<<<<<<<< next is null
        t->Tnext->Tcount++;
        t->Tparamtypes = paramtypes;
    }
    ctype = t;
    return t;
}
...