[llvm-dev] llvm-strip creates unloadable shared objects on linux-armv7hf

[Rui Ueyama via llvm-dev]

I'm not ARM expert, but yes I guess so.

On Thu, Oct 17, 2019 at 6:16 PM Tobias Hieta <tobias at plexapp.com> wrote:

> Hello Rui,
>
> Thanks for your reply. I tried with the keep-section argument and that
> made the shared library work.
>
> Should these sections be kept around by default maybe?
>
> -- Tobias
>
> On Thu, Oct 17, 2019 at 11:06 AM Rui Ueyama <ruiu at google.com> wrote:
> >
> > One thing I noticed is that llvm-strip seemed to remove a
> .ARM.attributes section. Can you try --keep-section=.ARM.attributes to tell
> to the command to keep the section?
> >
> > On Thu, Oct 17, 2019 at 5:37 PM Tobias Hieta via llvm-dev <
> llvm-dev at lists.llvm.org> wrote:
> >>
> >> Hello,
> >>
> >> Recently we tried to streamline our toolchain by removing some GNU
> >> tools with LLVM tools to avoid having multiple copies of strip, nm, ar
> >> and similar tools. Today we ran into a really strange issue where
> >> shared objects where not loadable.
> >>
> >> We where able to track this down to llvm-strip with default arguments
> >> creating a shared object that doesn't load correctly. It works if we
> >> switch from not passing args to llvm-strip to pass -strip-all-gnu
> >>
> >> I built bzip2 and libbz2.so to show this case here:
> >> https://1drv.ms/u/s!Amjta5FRkBbbkiz14aHTRJe03LlL?e=2mGvTN
> >>
> >> This is the error we got by using the stripped shared object with
> >> llvm-strip -strip-all:
> >>
> >> admin at Netgear-RN212:~/b$ LD_PRELOAD=./libbz2.so.all ./bzip2
> >> ERROR: ld.so: object './libbz2.so.all' from LD_PRELOAD cannot be
> >> preloaded (cannot open shared object file): ignored.
> >> ./bzip2: error while loading shared libraries: libbz2.so: cannot open
> >> shared object file: No such file or directory
> >>
> >> And with strip-all-gnu it works:
> >> admin at Netgear-RN212:~/b$ LD_PRELOAD=./libbz2.so.all_gnu ./bzip2
> >> bzip2: I won't write compressed data to a terminal.
> >> bzip2: For help, type: `bzip2 --help'.
> >>
> >> This only seems to happen on Linux-armv7hf - we haven't seen this on
> >> any of the intel platforms.
> >>
> >> Thanks,
> >> Tobias
> >> _______________________________________________
> >> LLVM Developers mailing list
> >> llvm-dev at lists.llvm.org
> >> https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20191017/b3ce48b5/attachment.html>