From: David Gibson <david@gibson.dropbear.id.au>
To: ccan@lists.ozlabs.org
Subject: Re: dgraph, tlist, tcon: MSVC error due to array of flexible structs
Date: Tue, 1 Aug 2017 15:22:05 +1000 [thread overview]
Message-ID: <20170801052205.GO2652@umbus.fritz.box> (raw)
In-Reply-To: <20160923043116.ytrxrm7dsgusdrif@kevinolos>
[-- Attachment #1.1: Type: text/plain, Size: 1885 bytes --]
On Thu, Sep 22, 2016 at 10:31:16PM -0600, Kevin Locke wrote:
1;4803;0c> Hi all,
>
> Building dgraph using Microsoft Visual C++ produces the following
> error:
>
> dgraph.h(25): error C2233: 'edge': arrays of objects containing
> zero-size arrays are illegal
>
> The issue is that MSVC supports flexible array members, but does not
> support arrays of structs with flexible array members. My
> understanding is that such support is not required by C99 or C11, but
> I don't know whether such support is common beyond Clang/GCC.
>
> Is there any interest in supporting such compilers? If so, I can see
> a few potential fixes:
>
> 1. Change TCON to use flexible array members only when the compiler
> supports arrays of structs with flexible array members. This is an
> easy fix, but wastes space for every TCON/TLIST usage on such
> compilers.
>
> 2. Have TCON (and TLIST) provide an alternative macro which uses
> flexible array members only when supported in arrays, and use that in
> dgraph. It would increase the API and duplicate a bit of code, but
> would only waste space when TCON/TLIST are placed in arrays.
>
> 2. Replace the 2-element edge array in struct dgraph_node with
> separate fields edge_from and edge_to. This complicates the logic a
> bit, since it is no longer symmetric with dgraph_edge. It would also
> be an incompatible API change.
>
> 3. Change TLIST to use TCON_WRAP? I don't understand TLIST/TCON well
> enough to know if this is really an option. Hopefully an expert can
> weigh in here.
I've now done this for tlist and several other modules, we should have
a much better chance of compiling on windows.
--
David Gibson | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_
| _way_ _around_!
http://www.ozlabs.org/~dgibson
[-- Attachment #1.2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]
[-- Attachment #2: Type: text/plain, Size: 127 bytes --]
_______________________________________________
ccan mailing list
ccan@lists.ozlabs.org
https://lists.ozlabs.org/listinfo/ccan
next prev parent reply other threads:[~2017-08-01 5:22 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-09-23 4:31 dgraph, tlist, tcon: MSVC error due to array of flexible structs Kevin Locke
2016-09-27 4:45 ` David Gibson
2016-09-28 2:10 ` Rusty Russell
2016-09-28 3:12 ` David Gibson
2017-08-01 5:22 ` David Gibson [this message]
2017-08-02 5:38 ` Kevin Locke
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=20170801052205.GO2652@umbus.fritz.box \
--to=david@gibson.dropbear.id.au \
--cc=ccan@lists.ozlabs.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.