Don't populate the typenames array for each and every created object and don't
search it when deleting every object, this is O(N) in number of classes and is
completely impractical for any big library where N can easily be several
thousands. Use destructor function which will correctly destroy the object
instead.
Also don't store each created objects in the global registry, there doesn't
seem to be any point in it.
And, in fact, don't bother with the typenames at all, just use another
pseudo-virtual function for checking whether a class inherits from a class
with the given name.
There is unfortunately one problem with the new approach: it doesn't work when
the same C++ type is wrapped under different names as this results in multiple
specializations of SWIG_derives_from<> for this type. But this is a relatively
rare situation (but which does arise in template_default2 unit test, which had
to be disabled) and could be fixed in the future by completely resolving the
type, including the default template parameters values, and checking if
SWIG_derives_from had been already specialized for it. In the meanwhile, this
regression is not a big deal compared to the advantages of the new approach.
The proxy layer, and all the extra complexity associated with it, seemed to be
only necessary in order to try to allow using the same name for the wrapped
global functions as were used for them in the original C or C++ code being
wrapped. However this could simply never work in all cases, notably it didn't
work at all when using ELF shared libraries under Unix as the functions with
the same name defined in the main program were interposed and replaced the
functions defined in the shared library, meaning that the proxy function foo()
called wrapper function _wrap_foo() which called back into proxy function
foo() itself again, resulting in guaranteed stack overflow. The only possible
way to fix this would be to use "protected" ELF visibility for the original
functions, but this is not always possible (e.g. if the sources of the
original library are not available) and not simple even when it is and,
besides, protected visibility has its own problems -- notably by making it
impossible to hook the library functions when you actually want to do it.
Besides, proxy-based approach simply couldn't work at all when using static
linking as it resulted in two copies of the function with the same name
Most importantly, however, the main task of this module is to wrap C++
classes, not C functions, and renaming them in the wrapper is not necessary at
all in this case as there is no conflict with the original names in this case.
So simply drop the idea of generating a separate proxy header and generate a
header declaring the functions declared in the wrapper instead and, also, do
not give them "_wrap_" prefix whenever possible, i.e. only do it for the
global functions.
This simplifies SWIG code itself and makes it simpler to use its output as
it's not necessary to link both with the wrapper (dynamically) and with the
proxy (statically) and it's not enough to link with the wrapper only and it
can be done in any way (i.e. either statically or dynamically).
As a side effect of this change, Swig_name_proxy() is not necessary any more
and was removed, eliminating the only difference with the master branch in any
source file other than c.cxx itself.
