Re: RFC: on AIX, which "soname"-equivalent to prefer with runtime linking?

[Michael Haubenwallner]

On 01/21/11 17:48, Robert Boehne wrote:
> Michael,
> The "-brtl" isn't a "run-time linking" flag, but more exactly, it's a 
> system-5 shared library compatibility mode flag.
> It is intended to provide a more familiar shared library style, not 
> additional features.

As far as I can tell, runtime linking is not done on AIX without the '-brtl' 
flag
to both the shared objects and the executable. Eventually it is the '-brtllib' 
flag
that actually /enables/ runtime linking for an executable (which is added by the
'-brtl' flag and gets disabled with '-bnortllib' when creating shared objects, 
either
explicitly or via '-G' linker flag), but '-brtl' is still necessary to /allow/ a
shared object to be subject to runtime linking.

But yes, '-brtl' also adds some extra System-V compatibility at linktime,
however something like 'DT_SONAME' is still missing.

/haubi/

> With AIX style shared libraries, you can put multiple versions of a shared 
> library, and static versions,
> in the same archive file, 32 bit & 64 bit etc.  AIX shared libraries are very 
> flexible, however,
> because no other operating system (to my knowledge) supports the same 
> features, those features are not portable.
> 
> HTH,
> 
> Rob
> 
> On Fri, Jan 21, 2011 at 8:19 AM, Michael Haubenwallner <address@hidden 
> <mailto:address@hidden>> wrote:
> 
>     Hello!
> 
>     On AIX, with runtime linking (-brtl linker flag) enabled, the current way
>     how libtool creates shared libraries prevents any form of "soname" 
> support,
>     as there is no way to have the runtime loader to load a different version 
> of
>     some shared object (either standalone or as archive member) than the 
> linker
>     would record into the next binary when linking against this library.
> 
<snip>