mail archive of the barebox mailing list
 help / color / mirror / Atom feed
From: Peter Mamonov <pmamonov@gmail.com>
To: Ahmad Fatoum <a.fatoum@pengutronix.de>
Cc: barebox@lists.infradead.org
Subject: Re: RFC: types conflicts
Date: Thu, 9 Jul 2020 00:02:32 +0300	[thread overview]
Message-ID: <20200708210231.GA24761@chr> (raw)
In-Reply-To: <c50f7807-9bfa-bc70-d771-f798422760e1@pengutronix.de>

Hello, Ahmad,

On Wed, Jul 08, 2020 at 10:02:00AM +0200, Ahmad Fatoum wrote:
> Hello Peter,
> 
> On 7/7/20 3:56 PM, Peter Mamonov wrote:
> > Hello,
> > 
> > I tried to build MicroPython using barebox toolchain and found a number of
> > conflicts between barebox and compiler headers. Below you will find the patch
> > which demostrates some of them. In this particular example the problem arises
> > due to simultaneous inclusion of some compiler headers along with barebox
> > version of `strings.h`, which in turn includes barebox analogs of those headers
> > from `include/linux`. I belive there should be a segregation between headers in
> > `include` and in `include/linux`, i.e. headers from `include/` should not
> > reference <linux/*.h> headers. Yet I understand this is somewhat problematic.
> > What do you think?
> 
> barebox code shouldn't make use of any compiler headers at all, except for <stdarg.h>.
> The only exception are arch/sandbox/os and scripts/, which reference libc headers.
> Everything else should comes out of barebox' include/ directory.
> 
> If you have foreign code that you want to port into barebox, either modify it
> to use barebox headers or change the include order when building it to use _local_
> versions of the headers it requires.

Ok, I've got your point. Yet I want to point out that addition of *unmodified* 
code in a form of git submodule would greatly simplify further support of this 
port. Unfortunately modifying include order will not help in this case, since, 
for example, both `barebox/include/linux/stddef.h` (included from 
`barebox/include/string.h` via <linux/string.h>, etc.) and 
`/usr/lib/gcc-cross/<ARCH>-linux-gnu/X/include/stdbool.h` define `true`/`false` 
macros. On the other hand `/usr/include/linux/stddef.h` and 
`/usr/lib/gcc/<ARCH>-linux-gnu/X/include/stdbool.h` coexist in GNU/Linux system 
nicely, since no header from `/usr/include/` does reference <linux/*.h> 
headers.

> > diff --git a/commands/types_conflict.c b/commands/types_conflict.c
> > new file mode 100644
> > index 0000000000..70fee8d6f4
> > --- /dev/null
> > +++ b/commands/types_conflict.c
> > @@ -0,0 +1,12 @@
> > +#include <stdbool.h>
> > +#include <stdint.h>
> > +#include <stddef.h>
> > +
> > +#include <string.h>
> 
> barebox (except sandbox) is meant to be compiled with freestanding C implementations
> that aren't required to provide a <string.h>. So no barebox code should depend on
> compiler-provided <string.h>.

Actually `string.h` comes from barebox's `include/` dir, while `std*.h` come 
from compiler's include dir. 


PS: By the way, do you think Barebox will benefit from importing MicroPython 
(https://micropython.org/) and exposing some of Barebox APIs to it?

Regards,
Peter

_______________________________________________
barebox mailing list
barebox@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/barebox

  reply	other threads:[~2020-07-08 21:02 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-07-07 13:56 Peter Mamonov
2020-07-08  8:02 ` Ahmad Fatoum
2020-07-08 21:02   ` Peter Mamonov [this message]
2021-04-19  7:58     ` Ahmad Fatoum
2021-04-20 21:47       ` Peter Mamonov

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20200708210231.GA24761@chr \
    --to=pmamonov@gmail.com \
    --cc=a.fatoum@pengutronix.de \
    --cc=barebox@lists.infradead.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox