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Re: Re: -combine option for C++ sources
On Tue, 5 May 2009, Richard Guenther wrote:
> 2009/5/5 Pramod Joisha <pramod_joisha@hotmail.com>:
> >
> >
> > Presently, the -combine option works only for C sources. I was
> > wondering whether there are technical reasons for not supporting it
> > for C++ sources. If not, are there plans for providing this support in
> > the near future?
>
> As LTO will obsolete -combine I do not see that -combine will be
> ever implemented for anything else besides C.
Formally there are things -combine does that LTO doesn't
(front-end-specific consistency checks across translation units,
supporting non-ELF targets). But I agree we should deprecate -combine
when LTO goes in (or better, deprecate the mechanism it uses and make the
driver transparently wrap LTO if possible); the consistency checks might
better be done through plugins, and there should be no great difficulty in
adding LTO support for non-ELF targets (that support arbitrary named
sections) if desired.
(The C++ front end should still grow some sort of support for handling
information from multiple translation units at once to implement exported
templates, but that's another matter.)
--
Joseph S. Myers
joseph@codesourcery.com