Re: Some more 2.1 <-> 2.2 Version differences

[Andreas Jaeger <aj at suse dot de>]

>>>>> Ulrich Drepper writes:

Ulrich> Andreas Jaeger <aj@suse.de> writes:
>> I checked now [1] the *map files for 2.1.3 and 2.2 and noticed a
>> problem with __libc_freeres, it got the wrong version number in
>> 2.1.3.  I'm appending a patch to synch this with glibc 2.2.

Ulrich> I applied the second part.  But the __libc_freeres change is not OK.
Ulrich> 2.1.3 was the first release where the function was exported.
Ulrich> Therefore the version name has to be GLIBC_2.1.3.  This is not
Ulrich> versioning is for since now GLIBC_2.1.3 is used as the most recent
Ulrich> versions in all binaries which use __libc_freeres and ld.so will
Ulrich> immediately stop if you run this program with a libc before 2.1.3.

The problem is malloc/Versions in glibc 2.1.3, it contains a GLIBC_2.1
instead of GLIBC_2.1.3:

  GLIBC_2.1 {
    # Special functions.
    __libc_freeres;
  }

glibc 2.1.3 has therefore:
$ readelf -a /lib/libc.so.6 |grep __libc_freeres
  000dc0a0  40c07 R_386_JUMP_SLOT       00054524  __libc_freeres           
  000c4a48  40c01 R_386_32              00054524  __libc_freeres           
  1036:    54524    81 FUNC    GLOBAL  0   16 __libc_freeres@@GLIBC_2.1
  5276:    54524    81 FUNC    GLOBAL  0   16 __libc_freeres

The bug is in glibc 2.1.3 - and for compatibility we should use the
same version number.

Are you sure this will work now?  AFAIK a program linked against glibc
2.1.3 using __libc_freeres will fail with glibc 2.2 since the versions
don't match.

Andreas
-- 
 Andreas Jaeger
  SuSE Labs aj@suse.de
   private aj@arthur.rhein-neckar.de