https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88054
Martin Liška <marxin at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
See Also| |https://sourceware.org/bugz
| |illa/show_bug.cgi?id=14932
--- Comment #5 from Martin Liška <marxin at gcc dot gnu.org> ---
The issue with dlvsym is that one can't request a default version (without
knowing ABI version), so e.g. dlvsym(h, "fopen", "").
I believe root problem is this glibc PR I just linked.
The problem is default version is not returned.
I wrote a script that lists all function names for which interceptor is called
(GetRealFunctionAddress) and I compared that to symbols in glibc that have
multiple interface versions. And the result is not good:
$ readelf --syms --wide /lib64/libc.so.6 | ./check-symver.py
['glob64@@GLIBC_2.27', 'glob64@GLIBC_2.2.5']
['glob@@GLIBC_2.27', 'glob@GLIBC_2.2.5']
['sched_getaffinity@@GLIBC_2.3.4', 'sched_getaffinity@GLIBC_2.3.3']
['realpath@@GLIBC_2.3', 'realpath@GLIBC_2.2.5']
['fmemopen@@GLIBC_2.22', 'fmemopen@GLIBC_2.2.5']
['memcpy@@GLIBC_2.14', 'memcpy@GLIBC_2.2.5']
$ readelf --syms --wide /lib/libc.so.6 | ./check-symver.py
['scandir64@@GLIBC_2.2', 'scandir64@GLIBC_2.1']
['glob64@@GLIBC_2.27', 'glob64@GLIBC_2.1', 'glob64@GLIBC_2.2']
['getpwent_r@@GLIBC_2.1.2', 'getpwent_r@GLIBC_2.0']
['getpwuid_r@@GLIBC_2.1.2', 'getpwuid_r@GLIBC_2.0']
['getgrnam_r@@GLIBC_2.1.2', 'getgrnam_r@GLIBC_2.0']
['shmctl@@GLIBC_2.2', 'shmctl@GLIBC_2.0']
['getgrent_r@@GLIBC_2.1.2', 'getgrent_r@GLIBC_2.0']
['glob@@GLIBC_2.27', 'glob@GLIBC_2.0']
['__lxstat64@@GLIBC_2.2', '__lxstat64@GLIBC_2.1']
['fclose@@GLIBC_2.1', 'fclose@GLIBC_2.0']
['gethostbyaddr_r@@GLIBC_2.1.2', 'gethostbyaddr_r@GLIBC_2.0']
['realpath@@GLIBC_2.3', 'realpath@GLIBC_2.0']
['gethostbyname_r@@GLIBC_2.1.2', 'gethostbyname_r@GLIBC_2.0']
['getpwnam_r@@GLIBC_2.1.2', 'getpwnam_r@GLIBC_2.0']
['readdir64@@GLIBC_2.2', 'readdir64@GLIBC_2.1']
['__xstat64@@GLIBC_2.2', '__xstat64@GLIBC_2.1']
['gethostbyname2_r@@GLIBC_2.1.2', 'gethostbyname2_r@GLIBC_2.0']
['getgrgid_r@@GLIBC_2.1.2', 'getgrgid_r@GLIBC_2.0']
['fopen@@GLIBC_2.1', 'fopen@GLIBC_2.0']
['fmemopen@@GLIBC_2.22', 'fmemopen@GLIBC_2.2']
['readdir64_r@@GLIBC_2.2', 'readdir64_r@GLIBC_2.1']
['fopencookie@@GLIBC_2.2', 'fopencookie@GLIBC_2.0']
['gethostent_r@@GLIBC_2.1.2', 'gethostent_r@GLIBC_2.0']
['fdopen@@GLIBC_2.1', 'fdopen@GLIBC_2.0']
['sched_getaffinity@@GLIBC_2.3.4', 'sched_getaffinity@GLIBC_2.3.3']
