Re: Master fails to compile

[Keith OHara]

On Thu, 28 May 2015 01:36:54 -0700, David Kastrup <address@hidden> wrote:

> "Keith OHara" <address@hidden> writes:
>
> > I had an old RedHat installation with gcc updated as far as I could to
> > 4.6.  In the next few weeks I'll find some reasonably-modern linux.
>
> Well, using no longer supported systems with network access (and it's
> pretty hard to work on current LilyPond source without network access)
> is a security nightmare.  Old GNU/Linux installations are actually
> pretty popular as mail hubs for malware distribution.

Updating most software, was no problem, even synchronizing to the release of 
the whole distribution.  But gcc and glibc tend to lag behind.  The latest 
Centos that works on a 32-bit i386 is CentOS 6.6 (supported through 2020) with 
gcc 4.4.7.  I'm looking into switching to Debian.

> > The tricky bit about the function template in Smob_base template <SCM
> > (Super::*pmf)(void)> static SCM smob_trampoline (SCM self) is the way
> > it creates functions in Smob_base that call member functions of the
> > derived classes like Listener.  Following what happens requires a lot
> > of flipping back and forth between header files.
>
> Smob_base may not be the best place.  I remember wanting to put it in
> Dispatcher itself at first and I got some private/protected thing in the
> way.  But it might make more sense to pierce the encapsulation with some
> sort of "friend" declaration (if unavoidable) rather than move the whole
> functionality there.

If you can define the trampoline as a static member of the class whose member 
function is being called, that will be less surprising.   It might be a bit 
ugly to have the boiler-plate code in each derived class that uses the 
mechanism, but the boilerplate is recognizable if we can see it all at once.
   LY_DECLARE_SMOB_APPLY_INIT(smob_apply_trampoline, 1, 0, 0)
   static SCM smob_apply_trampoline(SCM self, SCM arg) {
     return unsmob(self)->listen(arg);
   }
   SCM listen(SCM ev) {
    ...}