Re: [PATCH 0/8] Fix build with using OCaml 4.06.1 and -safe-string

[Julien Grall <julien@xxxxxxx>]

Hi Ian,

On 31/03/2020 12:17, Ian Jackson wrote:
> Julien Grall writes ("[PATCH 0/8] Fix build with using OCaml 4.06.1 and 
> -safe-string"):
> > This series is meant to solve the build issue reported by Dario when
> > using recent version of OCaml and -safe-string.
> Thanks.  I have reviewed the C tools parts here.  I think the ocaml
> parts ought to have a review from someone familiar with the ocaml FFI.
>
> > I took the opportunity to harden a bit more the code by using const more
> > often.
> I approve.
>
> Perhaps we should start building our C code with -Wwrite-strings,
> which makes "" have type const char* ?  Result would be a giant
> constification patch, probably.
So I thought I would give a try and see how far I can go:

   * hypervisor (xen): It is fairly easy to convert, although this is 
touching code that was imported from other projects (such as acpica). I 
need to have a look at whether other projects fixed there code and we 
can backport.
   * libxc: This is pretty trivial, I will send a patch for it
   * libxl: This is where it is getting tricky, the main issue is the 
flexarray framework as we would use it with string (now const char *). I 
thought we could make the interface const, but it looks like there are a 
couple of places where we need to modify the content (such as in 
libxl_json.c). I am not sure yet how to deal with it.
In any case, even if we can't use -Wwrite-strings, I can still send 
patches to use const in more places.
Cheers,

--
Julien Grall