From: address@hidden At: Jul 6 2015 10:50:50
On 06/24/2015 03:34 PM, Daniel Ruoso (BLOOMBERG/ 731 LEX) wrote:
> This patch offers a simplified implementation of a SONAME-like behavior emulation.
I've tried this variant of soname-emulation too, but discovered the one using
the "lib.so.v(shr.o,shr.imp)" archive (=svr4) as the more reasonable compromise.
Is there a specific reason you need/want this simplified implementation?
The main reason is actually non-libtool build systems, where I have to implement this
by hand. The .so as text file is a much simpler implementation for situations where I have
to torture a hand-rolled build-system into producing a versionable shared object.
> This is different in the sense that it doesn't add archives disguised as .so files,
Yeah, instead it does provide plain text files disguised as .so files.
Besides that, there's potential for more different confusion:
*) Linking with "/path/to/lib.so" produces different result than
linking with "/path/to/lib.so.v" (difference is in the runpath).
*) dlopen("lib.so") fails, while dlopen("lib.so.v") does work.
*) Provides two distinct files, instead of one single file with symlinks.
Those are fair points, I haven't considered them since all my AIX builds happen in very
controlled setups.
I could maybe argue that the dlopen case is a degenerate case, because the
runtime interface of a versioned shared library is its SONAME, not the unversioned .so,
and for shared objects that are intended to be dlopen'ed (which libtool calls modules),
my patch won't affect them.
> and instead relies on the fact that the AIX linker will take an import file when
> looking for -l<foo>, and will record what the import file says.
This very detail isn't anything different compared to aix-soname=svr4.
Fair point again...
I think the main problem is that we implemented this patches in parallel, but I forgot to
release mine for a long time, and you did a much better job at it :).
I'll investigate how hard would it be to use your version of it for libtool projects
(even if I still do the simplified version for hand-rolled build systems).
daniel