V3 ABI

Per Bothner per@bothner.com
Thu Dec 7 18:38:00 GMT 2000


Bryce McKinlay <bryce@albatross.co.nz> writes:

> Right, the "typeinfo pointer" field is at a -1 offset (from the vtable
> address). However, I figured that this would be where the java class
> pointer would go?

That doesn't seem to be what people have been suggesting.  If I
understand Alex right, the idea is we add two vtable entries by (at
offsets 0 and 1) by adding (in Object.h for C++) two fake methods.
The two entries would actually point to the Class and the GC info.

> Then again, if we want that to actually make  proper
> C++ RTTI type_info objects,

At some point, I think we should.  If nothing else, to clean up
the exception handling, so that the run-time can determine on
a handler-by-handler basis if the exception handled is specified
by a C++ rtti or a Jaca Throwable.  To do that, I think we need to
define some variant of C++ rtti, that specifies that the exception
type is a Java class, and in a way that won't confuse C++ code.
(This is rather vague, but then I don't know the current status
of the code.)
-- 
	--Per Bothner
per@bothner.com   http://www.bothner.com/~per/


More information about the Java mailing list