[LLVMdev] Name of the libraries + soname? 3.4.1 ?

[Sylvestre Ledru]

On 12/05/2014 16:13, Tom Stellard wrote:
> On Mon, May 12, 2014 at 04:05:20PM +0200, Sylvestre Ledru wrote:
>> On 12/05/2014 15:22, Tom Stellard wrote:
>>> On Mon, May 12, 2014 at 08:41:36AM +0200, Sylvestre Ledru wrote:
>>>> Hello,
>>>>
>>>> With the release of 3.4.1, the LLVM library has been renamed from
>>>> libLLVM-3.4.so to libLLVM-3.4.1.so. In parallel, the soname has been
>>>> updated to
>>>> reflect this change.
>>>>
>>>> AFAIK, we kept the ABI compatible from 3.4 to 3.4.1. So, is there any
>>>> reason for doing it?
>>>> This caused some breakages in Debian (basically, breaking some X because
>>>> of mesa could not
>>>> link against LLVM due to the new soname).
>>>> I noticed that we did the same with 3.5.
>>>>
>>>> I am not sure to understand what was wrong with the X.Y naming schema.
>>>
>>> The library was renamed, but a libLLVM-3.4.so symlink was added to point
>>> to libLLVM-3.4.1.so, so I don't think anything should break.
>> Yes but the (distro?) tools relies on the soname for linking and the
>> soname was updated.
> 
> Is soname an attribute that is stored somewhere within the shared library, or does
> it refer to the name of the shared object file?
It is stored inside (and built with -Wl,-soname,libfoo.so.0)
For example, in Debian (and Ubuntu), we consider that a library in
/usr/lib/* without a soname is an error.

Example:
$ objdump -p /usr/lib/x86_64-linux-gnu/libLLVM-3.4.so.1 |grep SONAME
  SONAME               libLLVM-3.4.so.1

Cheers,
Sylvestre