Change the numbering of static ctors/dtors to be module based instead of being global. This fixes #210 by making sure that the static ctor always gets the same number, regardless of the order of the modules given at the command line.

module structs7;

struct S
{
    int i;
    long l;
}

void main()
{
    S s = void;
    int i = s.i;
    long l = s.l;
}