From: Rich Felker <dalias@libc.org>
To: Harald Welte <laforge@gnumonks.org>
Cc: musl@lists.openwall.com
Subject: Re: [musl] MUSL ignores__attribute__((constructor(priority))) ?
Date: Fri, 22 May 2020 13:33:00 -0400 [thread overview]
Message-ID: <20200522173300.GX1079@brightrain.aerifal.cx> (raw)
In-Reply-To: <20200522165006.GR2993937@nataraja>
On Fri, May 22, 2020 at 06:50:06PM +0200, Harald Welte wrote:
> Hi Rich,
>
> On Thu, May 21, 2020 at 05:49:48PM -0400, Rich Felker wrote:
> > > According to the OpenWRT build I have been provided by a 3rd party, it's
> > > using musl-1-1.23.
> >
> > Can you confirm this to make sure we're not debugging an issue that's
> > long since fixed? Run /lib/ld-musl-armhf.so.1 as a command and it will
> > print its version.
>
> *sigh*. It was 1.1.20. This specific (vendor) OpenWRT tree was broken in that
> it used the 1.1.20 source code but called the generated packages and
> path names 1.1.23 :/
>
> After updating the sources to actual 1.1.23, the constructor order is
> correct and I can run the unmodified libraries + application just like
> on glibc.
>
> Sorry for the noise then. Normally if something is named 1.1.23 you
> assume it also is 1.1.23 inside...
OK, I'll inquire with OpenWRT about what's going on here..
> > FWIW the only standards that musl purports to actually adhere to are
> > C, POSIX, and IEEE 754 (as referenced by C Annex F). While ELF is the
> > binary format used and we aim to use it in compatible ways so as not
> > to be gratuitously breaking, there are a lot of details that do not
> > match historical SysV behavior (this is also true on glibc to a lesser
> > extent), e.g. historical RPATH vs RUNPATH difference, LD_* vars, etc.
>
> Does that explain why trying to LD_PRELOAD libtalloc didn't fix the
> ordering either? It was one humble attempt at manually overriding the
> order (on 1.1.20).
Yes, old behavior was execution in reverse load order. This gave
something like dependency order for some very simple dependency
structures, but for LD_PRELOAD it resulted in the preloaded library's
ctors running _last_.
Rich
next prev parent reply other threads:[~2020-05-22 17:33 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-05-21 20:22 Harald Welte
2020-05-21 20:40 ` Rich Felker
2020-05-21 21:19 ` Harald Welte
2020-05-21 21:49 ` Rich Felker
2020-05-22 16:50 ` Harald Welte
2020-05-22 17:33 ` Rich Felker [this message]
2020-05-22 17:45 ` Hauke Mehrtens
2020-05-22 17:53 ` Rich Felker
2020-05-22 23:37 ` Alexander 'lynxis' Couzens
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=20200522173300.GX1079@brightrain.aerifal.cx \
--to=dalias@libc.org \
--cc=laforge@gnumonks.org \
--cc=musl@lists.openwall.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.
Code repositories for project(s) associated with this public inbox
https://git.vuxu.org/mirror/musl/
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).