Re: C++ conversion status update

John Baldwin
2016-04-19T21:40:34Z

On Tuesday, April 19, 2016 09:36:33 PM Pedro Alves wrote:
> On 04/19/2016 07:22 PM, John Baldwin wrote:
> > Thanks, I was able to test it and it works great on FreeBSD/amd64.
>
> Great, thanks for confirming.
>
> > The only remaining issue is that FreeBSD's stack_t defines ss_sp as char *
> > instead of void *. Apparently 4.4BSD had this and the other BSD's fixed this
> > long ago. When I first ran into this in January I fixed FreeBSD's trunk, so
> > 11.0 will ship with a proper ss_sp of void *, but older releases will not.
> >
>
> > The affected code is in setup_alternate_signal_stack() in gdb/main.c where
> > ss_sp is assigned to the void * returned from xmalloc().
> >
> > I was torn between just supporting C++ builds on FreeBSD 11 and later, or
> > adding autoconf glue for just this part. However, given that it seems like
> > the recent discussion is to deprecate C mode in the near future, it seems
> > like I should do the latter. Do you have any better suggestions?
> >
>
> C++ allows conversion to 'void *' without a cast. So I think
> we just need to do:
>
> - ss.ss_sp = xmalloc (SIGSTKSZ);
> + ss.ss_sp = (char *) xmalloc (SIGSTKSZ);
>
> and it'll work on both char * and void * hosts. I tried it
> here on GNU/Linux, where ss_sp is void *, and it works.
>
> Would you like to send that as a patch (with a comment)?
>
> We can leave adding an autoconf check if some other host uses
> a type different than void * and char *.

Ok, I will include that in my current patchset.

--
John Baldwin