From: Nathan Sidwell <nathan@acm.org>
To: Alexandre Oliva <oliva@adacore.com>
Cc: gcc-patches@gcc.gnu.org, jason@redhat.com,
joseph@codesourcery.com, ebotcazou@adacore.com
Subject: Re: [PATCH] introduce attribute exalias
Date: Sat, 15 Aug 2020 17:11:03 -0400 [thread overview]
Message-ID: <4647d37b-13af-e485-c782-c222360b12b9@acm.org> (raw)
In-Reply-To: <or5z9kvdbn.fsf@livre.home>
On 8/14/20 10:43 PM, Alexandre Oliva wrote:
> On Aug 14, 2020, Nathan Sidwell <nathan@acm.org> wrote:
> Since you don't seem to have liked 'aka' either, how about 'nickname',
> or 'nicknamed'? A more convenient name to refer to an entity is exactly
> what this is about, eh?
I'm sorry, I think those are awful names. They convey no intent. C++ already
has at least 2 'nickname' mechanisms:
using bob = ::foo::bar<bob::random_type,int>;
auto &bill = ::elsewhere::object<some_type>;
'alias' is also now a confusing term, because of the concept of object-aliasing.
The existing alias attribute is defined as:
> The @code{alias} attribute causes the declaration to be emitted as an alias
> for another symbol, which must have been previously declared with the same
> type, and for variables, also the same size and alignment. Declaring an alias
> with a different type than the target is undefined and may be diagnosed. As
> an example, the following declarations:
I.e. it is creating a declaration that is aliased to some other symbol (which
has to also be emitted by the same TU due to the usual elf-like object file
semantics). Notice it says nothing about emitting a *symbol*.
The new attribute is emitting a symbol that equates the declaration it is
attached to (i.e. the other way round).
Its intent is to allow code written in another language to refer to this
definition. I imagine you'd commonly use the foreign language's mangling for
the string provided.
If we spell it 'X', consider:
[[gnu::X ("other")]] int i;
Most commonly, the assembly emitted would contain:
.globl other
.equiv other, i
so, perhaps we should spell it 'equiv'? That's using an existing term.
nathan
--
Nathan Sidwell
next prev parent reply other threads:[~2020-08-15 21:11 UTC|newest]
Thread overview: 35+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-07-29 20:56 [RFC, WIP] " Alexandre Oliva
2020-08-07 17:38 ` [PATCH] " Alexandre Oliva
2020-08-14 15:39 ` Alexandre Oliva
2020-08-14 16:24 ` Nathan Sidwell
2020-08-14 19:24 ` Alexandre Oliva
2020-08-14 22:12 ` Nathan Sidwell
2020-08-15 2:43 ` Alexandre Oliva
2020-08-15 9:22 ` Iain Sandoe
2020-08-15 16:39 ` Alexandre Oliva
2020-08-15 18:17 ` Iain Sandoe
2020-08-25 8:34 ` Alexandre Oliva
2020-08-25 11:23 ` Iain Sandoe
2020-08-15 17:26 ` Alexandre Oliva
2020-08-15 21:11 ` Nathan Sidwell [this message]
2020-08-25 7:50 ` Alexandre Oliva
2023-07-15 1:08 ` [PATCH v3] Introduce attribute reverse_alias Alexandre Oliva
2023-07-15 21:55 ` Nathan Sidwell
2023-07-18 4:29 ` Alexandre Oliva
2023-07-18 11:37 ` Richard Biener
2023-07-19 23:11 ` [PATCH v4] Introduce attribute sym Alexandre Oliva
2023-07-20 13:09 ` Richard Biener
2023-07-21 9:23 ` Alexandre Oliva
2023-07-22 3:12 ` Fangrui Song
2023-08-16 4:27 ` Alexandre Oliva
[not found] ` <orpm2tgrsd.fsf_-_@lxoliva.fsfla.org>
[not found] ` <CAH6eHdQ3vT3MjohuE-izto+K=BMRykY3T-UyWa5-=OTDPM-JsQ@mail.gmail.com>
[not found] ` <ory1h9t6nr.fsf@lxoliva.fsfla.org>
2023-09-20 5:59 ` [PATCH v5] Introduce attribute sym_alias (was: Last call for bikeshedding on attribute sym/exalias/reverse_alias) Alexandre Oliva
2023-11-20 12:54 ` [PATCH v5] Introduce attribute sym_alias Alexandre Oliva
2023-11-22 12:14 ` Richard Biener
2023-11-22 19:16 ` Joseph Myers
2023-11-22 13:13 ` [PATCH v5] Introduce attribute sym_alias (was: Last call for bikeshedding on attribute sym/exalias/reverse_alias) Jan Hubicka
2023-11-30 12:53 ` [PATCH v6] Introduce attribute sym_alias Alexandre Oliva
2023-11-30 15:24 ` Jan Hubicka
2023-12-01 11:25 ` [PATCH v7] " Alexandre Oliva
2023-12-06 2:10 ` [PATCH v8] " Alexandre Oliva
2023-12-06 10:06 ` [PATCH v7] " Jan Hubicka
2023-12-07 20:52 ` Alexandre Oliva
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=4647d37b-13af-e485-c782-c222360b12b9@acm.org \
--to=nathan@acm.org \
--cc=ebotcazou@adacore.com \
--cc=gcc-patches@gcc.gnu.org \
--cc=jason@redhat.com \
--cc=joseph@codesourcery.com \
--cc=oliva@adacore.com \
/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;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).