Re: libtool, -fstack-protector, -nostdlib, and while we're at it -Bdirect on SunOS

[Richard PALO <richard.palo%free.fr@localhost>]

Le 06/04/14 15:21, Joerg Sonnenberger a écrit :
> On Tue, Apr 01, 2014 at 07:02:22AM +0200, Richard PALO wrote:
> > 0001-add-fstack-protector-link-support-to-libtool.patch
> >    permits libtool to generate -fstack-protector* on all platforms.
>
> *sigh* Stupid, stupid, crappy specs. I dislike this. A lot. It should
> never have become a spec modifier. Is this for broken GCC instances
> outside pkgsrc or for the versions we have some control over?
Well, this patch only prevents libtool invoked with '--mode=link' from 
suppressing '-fstack-protector*' allowing the flag to be passed through 
unchanged to gcc/link where it will 'do the right thing'.

In particular, for SunOS, this permits gcc to add the following to the 
link statement: '-lssp_nonshared -lssp'.

I should reiterate that although this is sufficient for gcc, for g++ 
0003-remove-nostdlib-from-libtool-shared-libraries-for-fs.patch is 
needed as well in order to prevent g++ from consequently stripping via 
'-nostdlib' what it should be adding.

To answer your question, this particular patch (0001) is solely a 
libtool patch, which works with both native and pkgsrc gcc/g++.

In theory, and in my testing thus far on SunOS, this should simplify 
pkgsrc as opposed to complicate it given libtool won't swallow any 
longer the '-fstack-protector*' flag (which affected at very least perl 
and cups).

> > 0002-x86-64-sunos-fix-for-g-and-Wl-Bdirect-involving-libt.patch
> >    affects only SunOS x86_64 libtool, gcc47 & gcc48
>
> I believe the correct fix is the same I am going to apply for NetBSD
> soon -- to just not include GCC's unwinder in libgcc_s.

I'm not so sure, as this is the equivalent of the upstream gcc *and* 
libtool patch.

Here is the commit message for libtool:
> commit 525cddd2bcea4c565d6dd1d2d55dd1de1a476b67
> Author: Rainer Orth <ro%CeBiTec.Uni-Bielefeld.DE@localhost>
> Date:   Sat Jan 18 10:07:52 2014 +1300
>
>     libtool: opt_duplicate_compiler_generated_deps is harmful on Solaris
>
>     Fix for http://debbugs.gnu.org/cgi/bugreport.cgi?bug=16452.
>     * build-aux/ltmain.in (libtool_validate_options): disable the
>     opt_duplicate_compiler_generated_deps optimization for Solaris2 so
>     that gcc-4.9+ compiled C++ code with -Wl,-Bdirect on 64-bit Solaris
>     x86 can avoid unwinding failures caused by accidental mixing of the
>     libc and libgcc_s unwinders in a single executable.
>
>     Signed-off-by: Gary V. Vaughan <gary%gnu.org@localhost>

A link to the gcc bugreports is indicated in the patchset as well.
Again, this patcheset only affects SunOS platforms (gcc* and libtool).

cordially,

richard