What's the eaerliest GNAT that can be built with 4.9.3?

What's the eaerliest GNAT that can be built with 4.9.3?

[Lucretia]

As the subject really.

I've been declined to add Ada to Gentoo because of various reasons, one being the earliest compiler supported. The GNAT bootstrap Steve Arnold build is based on 4.9.3 which is a a good base version to have, but say if someone did want to build an earlier compiler will this build it?

I've successfully built 4.9.3 with that bootstrap and then using the built 4.9.3 to build 5.1.0, so that's good, just need to know the other way around.

Thanks,
Luke.

Re: What's the eaerliest GNAT that can be built with 4.9.3?

[Brian Drummond]

On Mon, 22 Aug 2016 09:25:43 -0700, Lucretia wrote:

> As the subject really.
> 
> I've successfully built 4.9.3 with that bootstrap and then using the
> built 4.9.3 to build 5.1.0, so that's good, just need to know the other
> way around.

Not a definitive answer but I would expect 4.8.x to build cleanly enough.

At the other extreme, I can report complete build failures of 4.3 (for 
AVR-Ada) with compilers of the 4.5 era onwards, because they stopped 
accepting negative enums (!!!) in the C sources which were present in the 
earlier compilers. 

So I would place 4.4 as a lower bound of what *might* build and 4.8 as a 
likely upper bound.

Between those, you probably have to bisect...

-- Brian

Re: What's the eaerliest GNAT that can be built with 4.9.3?

[Lucretia]

On Tuesday, 23 August 2016 12:33:08 UTC+1, Brian Drummond  wrote:
> On Mon, 22 Aug 2016 09:25:43 -0700, Lucretia wrote:
> 
> > As the subject really.
> > 
> > I've successfully built 4.9.3 with that bootstrap and then using the
> > built 4.9.3 to build 5.1.0, so that's good, just need to know the other
> > way around.
> 
> Not a definitive answer but I would expect 4.8.x to build cleanly enough.

4.8.5 builds, nothing before does.

Thanks,
Luke.