On Tue, 2010-06-29 at 11:40 +0200, Paolo Bonzini wrote: > On 06/29/2010 04:16 AM, Tom Tromey wrote: > > Ian> In Tom's interesting idea, we would write the mark function by hand > > for > > Ian> each C++ type that we use GTY with. > > > > I think we should be clear that the need to write a mark function for a > > new type is a drawback of this approach. Perhaps gengtype could still > > write the functions for ordinary types in GCC, just not (templatized) > > containers. > > Yes, gengtype would emit template specializations instead of its own > mangled function names, and it would just call the same function (e.g. > gt_mark) instead of using mangled names. The C++ front-end would pick > up the correct function.
It seems very complicated to me (and apparently different from current gengtype behavior), and I don't understand why should gengtype emit template specializations instead of simple code. Of course, I am only thinking of gengtype generated routines. Or probably I did not understood what you mean. Could you give a simple example please? > > For templated containers it would be the same, except that you'd have > overloading instead of full specialization, such as template<typename T> > mark(std::vector<typename T> v). gengtype logic can be simplified a > lot, if we accept that some of the error reporting will be deferred to > the compiler. Again, I don't understand very well. Why do C++ templates simplify gengtype's work? Cheers.
