Re: compile or not compile

[llewelly at xmission dot com]

Karol Szkudlarek <karol@mikronika.com.pl> writes:

> Eljay Love-Jensen wrote:
> 
> > Hi Karo,
> >
> > Add this to your class A:
> >
> > int foo(Items const&)
> > {
> >   std::cerr << "A::Items\n";
> >   return 0;
> > }
> >
> > HTH,
> > --Eljay
> >
> Hi!
> 
> I can't use you solution in my code because in real example I have
> little different sitiuation.
> In my second test case I try to explain more precisely my real
> case. Look at the following code:
> 
> // SECOND_CASE
> typedef int my_int;
> 
> class ALibraryClass
> {
> 
> public:
>     int foo(const my_int&)
>         {
>             return 0;
>         }
>     int foo(const bool&)
>         {
>             return 0;
>         }
> };
> 
> class BClientClass
> {
>     public:
>     enum Items
>     {
>         item1=1000,
>         item2=2000
>     };
>     void test()
>     {
>         ALibraryClass a;
>         a.foo(BClientClass::item1);

This should select A::foo(const my_int&) unambigously; enum to int is
    a promotion (see 4.5) while enum to bool is a conversion (4.12)
    and a promotion is a better match than conversion, (13.3.3.2/4).

>     }
> };
> 
> int main()
> {
>     BClientClass b;
>     b.test();
>     return 0;
> }
> 
> In class ALibraryClass I can't define int foo(Items const&)
> because I know nothing about enum Items from client class BClientClass.
> 
> 
> Generally I would like to know why this program compiles fine (gcc 3.3.3)
> under Debian but does not compile under Suse (gcc 3.3.3).  Is it possible
> such a difference in compiling results with the same versions of
> compiler?

You aren't really using the same compiler versions. For reasons known
    only to those who build distros, nearly every linux distro (and
    each BSD too!) maintains its own set of patches for gcc; what
    SUSE calls GCC 3.3.3 is actually a SUSE-special derivative of FSF
    GCC 3.3.3, what debian calls GCC 3.3.3 is a debian-special
    derivative of FSF GCC 3.3.3, and they are not really the same -
    only mostly the same. Most of the time, you won't run into the
    differences, but sometimes ...

FWIW, FSF GCC 3.3.3 and 3.4 like it, FBSD GCC 2.95.3 and 3.3.3 like
    it, and slackware-9.0 GCC 3.2.2 like it. I think you should report
    a bug to SUSE.