Mark Wielaard writes: > > On Fri, 2005-07-22 at 18:01 +0100, Andrew Haley wrote: > > Ingo Prötel writes: > > > > > I just implemented VMStackWalker for our VM and have some questions. > > > > > > The reference implementation of 'getCallingClass()' and > > > 'getCallingClassLoader()' just look at the third entry in the class > > > context. Would it not be better to return the first class that is not > > > assignable to the class in context[0] ? That way we could cope with > > > classes that first call some private or protected classes an then ends > > > up calling the stack walker. > > > > In gcj, we have a method called GetCallingClass(Class c). It searches > > firstly for a method declared in class c, then for a method not > > declared in c. We have found, after a certain amount of trouble, that > > this is the right way to do things; it means that an arbitrary number > > of stack frames can be between the direct caller of GetCallingClass > > and the user code, and it also means that you don't have to check for > > assignability, but for an exact match. > > I proposed something similar a while ago: > http://lists.gnu.org/archive/html/classpath-patches/2005-01/msg00138.html > > Jeroen did object strongly to this approach though since he felt that > having (and constructing) an extra argument for this function was too > much overhead for runtimes that didn't need it to begin with.
Well, that's up to the VM implementer. IMO trying to unify low-level stack walker code is unnecessary and leads to too many compromises; it's a merge too far. However, as for overhead -- I don't believe it. I doubt that not having this parameter saves anything much on any VM. Andrew. _______________________________________________ Classpath mailing list Classpath@gnu.org http://lists.gnu.org/mailman/listinfo/classpath
