deprecated symbols like pthread_mutexattr_getkind_np dropped in jammy

[Eric Covener]

Hello, I am linking with some object-code-only SDK that has references to pthread_mutexattr_getkind_np().

This symbol is in glibc-docs as deprecated (https://manpages.ubuntu.com/manpages/jammy/man3/pthread_mutexattr_setkind_np.3.html) but doesn't appear to be in libpthread.so . Is it intended to be dropped in jammy?

Description: Ubuntu 22.04.1 LTS
Release: 22.04

$ dpkg -l libc6
Desired=Unknown/Install/Remove/Purge/Hold
| Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend
|/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad)
||/ Name Version Architecture Description
+++-==============-===============-============-=================================
ii libc6:amd64 2.35-0ubuntu3.1 amd64 GNU C Library: Shared libraries
ii libc6:i386 2.35-0ubuntu3.1 i386 GNU C Library: Shared libraries

$ nm /usr/lib/x86_64-linux-gnu/libpthread.so.0 |grep pthread_mutexattr_getkind_np
$

On the prior LTS release, the symbol is present:

$ lsb_release -rd
Description: Ubuntu 20.04.5 LTS
Release: 20.04
$ dpkg -l libc6
Desired=Unknown/Install/Remove/Purge/Hold
| Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend
|/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad)
||/ Name Version Architecture Description
+++-==============-===============-============-=================================
ii libc6:amd64 2.31-0ubuntu9.9 amd64 GNU C Library: Shared libraries
ii libc6:i386 2.31-0ubuntu9.9 i386 GNU C Library: Shared libraries
$ nm /usr/lib/x86_64-linux-gnu/libpthread.so.0 |grep pthread_mutexattr_getkind_np
000000000000d350 W pthread_mutexattr_getkind_np

[Michael Hudson-Doyle (mwhudson)]

libpthread is trivial in 2.35. The symbol you mention seems to be in libc.so.6 now.

[Florian Weimer (fweimer)]

And pthread_mutexattr_getkind_np is a compatibility symbol now, not available for linking new applications. I think it's been deprecated for about 20 years when we restricted access.

[Eric Covener (covener)]

Thanks Florian, closing by converting to a question.