From: David Edelsohn <dje.gcc@gmail.com>
To: Richard Biener <richard.guenther@gmail.com>
Cc: Richard Biener <rguenther@suse.de>,
GCC Patches <gcc-patches@gcc.gnu.org>
Subject: Re: genmatch infinite loop during bootstrap on AIX
Date: Wed, 29 Oct 2014 17:31:00 -0000 [thread overview]
Message-ID: <CAGWvnykbZ2uMaoDNVgQxvRq5jNYUZXRq=SoFhKQXnnkjuPPoCQ@mail.gmail.com> (raw)
In-Reply-To: <CAFiYyc1e=trZ4GEObvO_eCenc=1yPzNj+UMu1_CdL9aC9x5wcQ@mail.gmail.com>
On Wed, Oct 29, 2014 at 9:24 AM, Richard Biener
<richard.guenther@gmail.com> wrote:
> Because only genmatch calls functions from libstdc++. Btw, why
> would genmatch miscompile an empty function or the call to it?
I tried bootstrapping with libstdc++ built without the AIX ld "-G"
flag and that is succeeding.
"-G" produces a shared object for use with SVR4-style runtime linking,
so this version of libstdc++ no longer allows runtime function
interposition, e.g., operator new, although it is not used frequently.
Something about the GCC-produced tail calls is interacting badly with
that feature.
Note that this makes GCC bootstrap on AIX very fragile at the moment
because it depends on how libstdc++ was built in previous releases. I
can bootstrap with GCC 4.6.3 and 4.8.1 but not with 4.7.3, 4.8.0, nor
4.9.0. A problematic libstdc++ from earlier releases causes genmatch
to loop in stage 1.
Thanks, David
next prev parent reply other threads:[~2014-10-29 17:13 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-10-24 23:37 David Edelsohn
2014-10-25 8:08 ` Richard Biener
2014-10-25 14:05 ` David Edelsohn
2014-10-25 15:16 ` David Edelsohn
2014-10-25 17:40 ` David Edelsohn
[not found] ` <CAGWvnynWYR5FYctJTa2GGvwGo3asvkU23Y-7Om8pLqCT3w-52A@mail.gmail.com>
2014-10-26 6:40 ` David Edelsohn
2014-10-26 10:37 ` Richard Biener
2014-10-27 1:36 ` David Edelsohn
2014-10-27 7:48 ` Richard Biener
2014-10-27 14:32 ` David Edelsohn
2014-10-27 14:56 ` David Edelsohn
2014-10-27 19:28 ` David Edelsohn
2014-10-27 20:13 ` Richard Biener
2014-10-27 23:36 ` David Edelsohn
2014-10-28 8:43 ` Richard Biener
2014-10-29 12:54 ` Richard Biener
2014-10-29 13:23 ` David Edelsohn
2014-10-29 13:31 ` Richard Biener
2014-10-29 17:31 ` David Edelsohn [this message]
2014-10-30 8:54 ` Richard Biener
2014-10-30 14:29 ` David Edelsohn
2014-10-31 8:54 ` Richard Biener
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