Re: [Caml-list] LLVM OCaml bindings

[Jacques-Pascal Deplaix <jp.deplaix@gmail.com>]

Hi,

I'm using LLVM for the compiler of my toy language Cervoise (link below).

First, before I started it, I heard from a friend that the official LLVM
binding can segfaults so I didn't want to use it [1].

I tried to create my own binding that produces LLVM-IR but there were
bugs (the interface didn't seems good).

So I tried the official binding. Like expected, it segfaults and has
several bugs and misses features [2] :/

Then, I tried to reproduce the interface of the LLVM binding but with
types parameters for lltype and llvalue to know what LLVM types can be
inserted for a function (the main cause of segfault), but it was very
very painful since we have to separate impossible cases and the type
errors (with recursive polymorphic variants) are awesome (irony) [3].

So now I have again my own binding that produces LLVM-IR but this time
with the same interface than the official binding, and it works pretty
well [4].

As a conclusion, don't try to add a type parameter like I did (however,
you can try other ways), it would be a waste of time.

[1]: We tried to fix this by starting TyLLVM (but it's not satisfying
and far to be finished): https://bitbucket.org/dinosaure/tyllvm
[2]: I have done several issues on the LLVM bug tracker, but apart from
segfaults and bugs when trying to use LLVM_bitwriter, the missed feature
is, IMHO, the possibility to get a string that contains the LLVM-IR
code, and not just print it.
[3]: https://github.com/jpdeplaix/cervoise/blob/jeSuisFou/src/LLVM.mli
[4]: https://github.com/jpdeplaix/cervoise/blob/master/src/LLVM.ml

On 11/05/2013 05:23 AM, Peter Zotov wrote:
> Hello folks,
>
> I'm currently working on improving LLVM's OCaml bindings.
> There's been quite some progress so far[1]; the only major
> areas pending are AOT code generation and MCJIT support.
>
> I would be very interested to hear how are you using these
> bindings, or suggestions for future development. In particular,
> I'd like to understand the impact of breaking the API.
>
>   [1]: https://github.com/llvm-mirror/llvm/commits/master/bindings/ocaml
>