Re: Merging gdc (GNU D Compiler) into gcc

[Iain Buclaw <ibuclaw at ubuntu dot com>]

On 5 October 2011 00:10, Ian Lance Taylor <iant@google.com> wrote:
> Iain Buclaw <ibuclaw@ubuntu.com> writes:
>
>> The active development of the D frontend would continue to be mirrored
>> in an external repository, but will occasionally be merged into GDC
>> project.
>
> Well, Go does set a precedent for this. ?The main issue here is that
> this means that there is (another) directory containing source code that
> the gcc maintainers can't update. ?This is workable if the D frontend
> does not #include any gcc header files or call any gcc functions. ?That
> is, if it is truly standalone. ?(The Go frontend is not yet in this
> state, although I am slowly working toward it.)
>
>

The D frontend does not include any gcc headers or call any gcc functions.

>> Some work would need to be done on naked functions at least first so
>> that changes required are only to gcc/config. I would be grateful if I
>> could get pointed in the right direction for implementing naked as a
>> function attribute for i386 so all frontends could benefit.
>
> Needs a target hook in target.def and a new attribute probably in
> c-family/c-common.c. ?The new attribute would check the target hook to
> see whether the backend supports it.
>
>
>>> The D runtime appears to be in a subdirectory of gcc/d. ?Ordinarily we
>>> would prefer that it be in a separate toplevel directory, e.g.,
>>> libdruntime.
>>>
>>
>> The set-up build script that is provided with the gdc development
>> folder makes symlinks from gcc/d/ to a libphobos toplevel directory.
>
> That is kind of awkward, though--why not just set up libphobos in the
> first place? ?I understand this may require two directories to be
> mirrored.
>
>

The gcc/d folder is only structured as it is now because gdc code is
shipped as a separate entity from gcc, that you can then apply to any
version of gcc that is supported.  This would no longer be the case if
merged in.  I assume best thing to do for me to get started in the
*doing* would be to set-up a new branch prep'd up as I intend for it
to be if this were to be moved forward.

>> First question that pops up after having a quick look is, are there
>> any tips around for writing the scripts for the testsuite? I'm not too
>> familiar with Dejagnu, and the current testsuite used for GDC D2
>> development is written in make.
>
> DejaGNU is too horrible for me to talk about. ?I can't recommend
> anything other than blind copying of existing scripts.
>

:-)

Regards
-- 
Iain Buclaw

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