Re: LLVM and Ada

[jparkerg000@gmail.com]

On Friday, October 21, 2016 at 9:32:04 AM UTC+1, vincent....@gmail.com wrote:
> Le jeudi 20 octobre 2016 20:20:44 UTC+2, Simon Clubley a écrit :
> 
> > There is no viable Ada frontend for current versions of LLVM (AFAIK)
> > although various people have looked at this.
> 
> Thank you Simon for your answer. 
> 
> Why Gnat on LLVM has been abandoned ? Was LLVM less appropriate than GCC for GNAT ?
> 
> My question precisely was not about the Ada frontend in fact but about a binding to use the LLVM from an Ada program that is a sort of compiler. I think that those who ported GNAT to LLVM should have created this kind of binding, no ?
> 
> Kind regards,
> 
> Vincent



The author of the GNAT LLVM compiler posted a few remarks on the subject in 2014. A search of comp.lang.ada should pull up the thread easily enough. I'll cut and paste the text for you.     J.



duncan...@deepbluecap.com 	
10/17/14
Hi,

> > That was the DragonEgg project, wasn't it? I got the impression it
>
> > foundered on some shortcoming of LLVM for non-C languages; not certain
>
> > which, but possibly the one regarding nested functions that Tristan has
>
> > overcome with ghdl.

no, there were no blocking technical problems.  For example I got nested function support working properly a gazillion years ago, as Luke says.  Exception handling took longer to be completely reliable, but that was also resolved years ago too.  In both cases changes needed to be made to LLVM, but those changes are all old hat now.  All that happened is that I lost interest in the project and no-one stepped forward to take it over.  That means that it's been quietly bit rotting for a while now.  For example: to accommodate internal changes in gcc-4.7 and later, dragonegg's ABI support needs to be rewritten, but I'd already lost interest in the project so never did it, which means that while it still mostly sorta works, thanks to some hacks, the plugin easily crashes on Ada tagged types starting from this gcc version.

Ciao, Duncan.