From: imp@bsdimp.com (Warner Losh)
Subject: [TUHS] why the leading under score added to function names?
Date: Mon, 20 Feb 2012 19:50:00 -0700 [thread overview]
Message-ID: <AAE63D3D-4F18-41E3-9059-7F885D6B29F5@bsdimp.com> (raw)
In-Reply-To: <96DE558D-5FE2-4F6F-BC83-18EC727162FA@coraid.com>
And this convention went away with ELF binaries. No more _foo for function foo.
Also, the fortran compiler would emit entry_ to as to not conflict either. Made calling C from Fortran, and vice versa, a lot of fun...
Warner
On Feb 20, 2012, at 5:34 PM, Brantley Coile wrote:
> correct. we could link to assembler code with _entry points and not worry about symbol collisions in the rest of the code.
>
> iPhone email
>
> On Feb 20, 2012, at 6:23 PM, "Dave Horsfall" <dave at horsfall.org> wrote:
>
>> On Mon, 20 Feb 2012, arnold at skeeve.com wrote:
>>
>> [...]
>>
>>> I'm pretty sure this dates back to PDP-11 days. I'm wondering "why?".
>>> Why did the C compiler prepend an underscore to function names?
>>
>> Sure was the PDP-11 :-) I vaguely recall that it was to make sure that
>> user functions did not conflict with predefined assembler functions, as
>> that would be a pain to diagnose (much like having swap overlap root).
>>
>> -- Dave
>> _______________________________________________
>> TUHS mailing list
>> TUHS at minnie.tuhs.org
>> https://minnie.tuhs.org/mailman/listinfo/tuhs
> _______________________________________________
> TUHS mailing list
> TUHS at minnie.tuhs.org
> https://minnie.tuhs.org/mailman/listinfo/tuhs
>
>
next prev parent reply other threads:[~2012-02-21 2:50 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-02-20 20:52 arnold
2012-02-20 23:21 ` Dave Horsfall
2012-02-21 0:34 ` Brantley Coile
2012-02-21 2:50 ` Warner Losh [this message]
2012-02-21 3:33 ` John Cowan
2012-02-21 3:41 ` Steve Nickolas
2012-02-21 18:18 ` ron
2012-02-22 19:17 arnold
2012-02-22 21:22 ` Dave Horsfall
2012-02-22 22:47 ` A. P. Garcia
2012-02-23 4:30 ` Greg 'groggy' Lehey
2012-02-25 18:45 ` Random832
2012-02-25 19:24 ` Steve Nickolas
2012-02-25 20:39 ` John Cowan
2012-02-25 22:15 ` Random832
2012-02-26 13:28 ` Ronald Natalie
2012-02-27 1:30 ` random832
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=AAE63D3D-4F18-41E3-9059-7F885D6B29F5@bsdimp.com \
--to=imp@bsdimp.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 NNTP newsgroup(s).