catching Objective-C objects in C++ catch statements (i.e. they follow
Objective-C semantics, not C++ semantics, irrespective of whether you use C++
or ObjC syntax). We now default to Apple-compatible behaviour, but provide a
function that allows users to select the sane semantics if they prefer.
Added a capability bit for the unified exception model, so code can require it.
This is not really required, since any code using it will link against the
ObjC++ personality function and will get a linker failure if it isn't supported.
Also enabled Objective-C++ stuff by default. This adds a dependency on the C++
standard library (actually on libsupc++, but GNUstep Make wants to link against
libstd++ anyway), which is not ideal. It can be disabled with:
$ gmake objectiver-cxx=no
I suggest that this is only done by people who know that they will never want
Objective-C++ support.
