It moves the missing CFLAGS from rt/Makefile to time/Makefile missing
from 7b5af2d8f2 (Finish move of clock_* functions to libc. [BZ #24959]).
Checked on powerpc64le-linux-gnu.
* rt/Makefile (CFLAGS-clock_nanosleep.c): Move to ...
* time/Makefile (CFLAGS-clock_nanosleep.c): ... here.
In glibc 2.17, the functions clock_getcpuclockid, clock_getres,
clock_gettime, clock_nanosleep, and clock_settime were moved from
librt.so to libc.so, leaving compatibility stubs behind. Now that the
dynamic linker no longer insists on finding versioned symbols in the
same library that originally defined them, we do not need the stubs
anymore, and this means we don't need GLIBC_PRIVATE __-prefix aliases
for most of the functions anymore either. (clock_gettime still needs
one.) For ports added before 2.17, libc.so needs to provide two
symbol versions for each, the default at GLIBC_2.17 plus a compat
version matching what librt had.
While I'm at it, move the clock_*.c files and their tests from rt/ to
time/.
With clock_getres, clock_gettime, and clock_settime refactor to remove the
generic CLOCK_PROCESS_CPUTIME_ID and CLOCK_THREAD_CPUTIME_ID support through
hp-timing, there is no usage of internal __get_clockfreq. This patch removes
both generic and Linux implementation..
Checked with a build against aarch64-linux-gnu, i686-linux-gnu, ia64-linux-gnu,
sparc64-linux-gnu, powerpc-linux-gnu-power4.
* include/libc-internal.h (__get_clockfreq): Remove prototype.
* rt/Makefile (clock-routines): Remove get_clockfreq.
* rt/get_clockfreq.c: Remove file.
* sysdeps/unix/sysv/linux/i386/get_clockfreq.c: Likewise.
* sysdeps/unix/sysv/linux/ia64/get_clockfreq.c: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc64/get_clockfreq.c: Likewise.
* sysdeps/unix/sysv/linux/powerpc/get_clockfreq.c: Move code to ...
* sysdeps/unix/sysv/linux/powerpc/get_timebase_freq.c: ... here.
As the result of commit 6e6249d0b4
("BZ#14743: Move clock_* symbols from librt to libc."), in glibc 2.17,
clock_gettime, clock_getres, clock_settime, clock_getcpuclockid,
clock_nanosleep were added to libc, and the file rt/clock-compat.c
was added with forwarders to the actual implementations in libc.
These forwarders were wrapped in
#if SHLIB_COMPAT (librt, GLIBC_2_2, GLIBC_2_17)
so that they are not present for newer architectures (such as
powerpc64le) with a 2.17 or later ABI baseline. But the forwarders
were not marked as compatibility symbols. As a result, on older
architectures, historic configure checks such as
AC_CHECK_LIB(rt, clock_gettime)
still cause linking against librt, even though this is completely
unnecessary. It also creates a needless porting hazard because
architectures behave differently when it comes to symbol availability.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Contributed by
Agustina Arzille <avarzille@riseup.net>
Amos Jeffries <squid3@treenet.co.nz>
David Michael <fedora.dm0@gmail.com>
Marco Gerards <marco@gnu.org>
Marcus Brinkmann <marcus@gnu.org>
Neal H. Walfield <neal@gnu.org>
Pino Toscano <toscano.pino@tiscali.it>
Richard Braun <rbraun@sceen.net>
Roland McGrath <roland@gnu.org>
Samuel Thibault <samuel.thibault@ens-lyon.org>
Thomas DiModica <ricinwich@yahoo.com>
Thomas Schwinge <tschwinge@gnu.org>
* htl: New directory.
* sysdeps/htl: New directory.
* sysdeps/hurd/htl: New directory.
* sysdeps/i386/htl: New directory.
* sysdeps/mach/htl: New directory.
* sysdeps/mach/hurd/htl: New directory.
* sysdeps/mach/hurd/i386/htl: New directory.
* nscd/Depend, resolv/Depend, rt/Depend: Add htl dependency.
* sysdeps/mach/hurd/i386/Implies: Add mach/hurd/i386/htl imply.
* sysdeps/mach/hurd/i386/libpthread.abilist: New file.
The types affected are __sig_atomic_t, sig_atomic_t, __sigset_t,
sigset_t, sigval_t, sigevent_t, and siginfo_t. __sig_atomic_t is a
scalar, so it's now directly available from bits/types.h. The others
get bits/types/ headers.
Side effects include: There have been small changes to which
non-signal headers expose which subset of the signal-related types.
A couple of architectures' nested siginfo_t fields had to be renamed
to prevent undesired macro expansion. Internal code that wants to
manipulate signal masks must now include <sigsetops.h> (which is not
installed) and should be aware that __sigaddset, __sigandset,
__sigdelset, __sigemptyset, and __sigorset no longer return a value
(unlike the public API). Relatedly, the public signal.h no longer
declares any of those functions. The obsolete sigmask() macro no
longer has a system-specific definition -- in the cases where it
matters, it didn't work anyway.
New Linux architectures should create bits/siginfo-arch.h and/or
bits/siginfo-consts-arch.h to customize their siginfo_t, rather than
duplicating everything in bits/siginfo.h (which no longer exists).
Add new __SI_* macros if necessary. Ports to other operating systems
are strongly encouraged to generalize this scheme further.
* bits/sigevent-consts.h
* bits/siginfo-consts.h
* bits/types/__sigset_t.h
* bits/types/sigevent_t.h
* bits/types/siginfo_t.h
* sysdeps/unix/sysv/linux/bits/sigevent-consts.h
* sysdeps/unix/sysv/linux/bits/siginfo-consts.h
* sysdeps/unix/sysv/linux/bits/types/__sigset_t.h
* sysdeps/unix/sysv/linux/bits/types/sigevent_t.h
* sysdeps/unix/sysv/linux/bits/types/siginfo_t.h:
New system-dependent bits headers.
* sysdeps/unix/sysv/linux/bits/siginfo-arch.h
* sysdeps/unix/sysv/linux/bits/siginfo-consts-arch.h
* sysdeps/unix/sysv/linux/ia64/bits/siginfo-arch.h
* sysdeps/unix/sysv/linux/ia64/bits/siginfo-consts-arch.h
* sysdeps/unix/sysv/linux/mips/bits/siginfo-arch.h
* sysdeps/unix/sysv/linux/sparc/bits/siginfo-arch.h
* sysdeps/unix/sysv/linux/tile/bits/siginfo-arch.h
* sysdeps/unix/sysv/linux/tile/bits/siginfo-consts-arch.h
* sysdeps/unix/sysv/linux/x86/bits/siginfo-arch.h:
New Linux-only system-dependent bits headers.
* signal/bits/types/sig_atomic_t.h
* signal/bits/types/sigset_t.h
* signal/bits/types/sigval_t.h:
New non-system-dependent bits headers.
* sysdeps/generic/sigsetops.h
* sysdeps/unix/sysv/linux/sigsetops.h:
New internal headers.
* include/bits/types/sig_atomic_t.h
* include/bits/types/sigset_t.h
* include/bits/types/sigval_t.h:
New wrappers.
* signal/sigsetops.h
* bits/siginfo.h
* bits/sigset.h
* sysdeps/unix/sysv/linux/bits/siginfo.h
* sysdeps/unix/sysv/linux/bits/sigset.h
* sysdeps/unix/sysv/linux/ia64/bits/siginfo.h
* sysdeps/unix/sysv/linux/mips/bits/siginfo.h
* sysdeps/unix/sysv/linux/s390/bits/siginfo.h
* sysdeps/unix/sysv/linux/sparc/bits/siginfo.h
* sysdeps/unix/sysv/linux/tile/bits/siginfo.h
* sysdeps/unix/sysv/linux/x86/bits/siginfo.h:
Deleted.
* signal/Makefile, sysdeps/unix/sysv/linux/Makefile:
Update lists of installed headers.
* posix/bits/types.h: Define __sig_atomic_t here.
* signal/signal.h: Use the new bits headers; no need to handle
__need_sig_atomic_t nor __need_sigset_t. Don't use __sigmask
to define sigmask.
* include/signal.h: No need to handle __need_sig_atomic_t
nor __need_sigset_t. Don't define __sigemptyset.
* io/sys/poll.h, setjmp/setjmp.h
* sysdeps/arm/sys/ucontext.h, sysdeps/generic/sys/ucontext.h
* sysdeps/i386/sys/ucontext.h, sysdeps/m68k/sys/ucontext.h
* sysdeps/mach/hurd/i386/bits/sigcontext.h
* sysdeps/mips/sys/ucontext.h, sysdeps/powerpc/novmxsetjmp.h
* sysdeps/pthread/bits/sigthread.h
* sysdeps/unix/sysv/linux/hppa/sys/ucontext.h
* sysdeps/unix/sysv/linux/m68k/sys/ucontext.h
* sysdeps/unix/sysv/linux/mips/sys/ucontext.h
* sysdeps/unix/sysv/linux/nios2/sys/ucontext.h
* sysdeps/unix/sysv/linux/powerpc/sys/ucontext.h
* sysdeps/unix/sysv/linux/s390/sys/ucontext.h
* sysdeps/unix/sysv/linux/sh/sys/ucontext.h
* sysdeps/unix/sysv/linux/sparc/sys/ucontext.h
* sysdeps/unix/sysv/linux/tile/sys/ucontext.h
* sysdeps/unix/sysv/linux/x86/sys/ucontext.h:
Use bits/types/__sigset_t.h.
* misc/sys/select.h, posix/spawn.h
* sysdeps/unix/sysv/linux/powerpc/sys/ucontext.h
* sysdeps/unix/sysv/linux/sys/epoll.h
* sysdeps/unix/sysv/linux/sys/signalfd.h:
Use bits/types/sigset_t.h.
* resolv/netdb.h, rt/mqueue.h: Use bits/types/sigevent_t.h.
* rt/aio.h: Use bits/types/sigevent_t.h and bits/sigevent-consts.h.
* socket/sys/socket.h: Don't include bits/sigset.h.
* login/utmp_file.c, shadow/lckpwdf.c, signal/sigandset.c
* signal/sigisempty.c, stdlib/abort.c, sysdeps/posix/profil.c
* sysdeps/posix/sigignore.c, sysdeps/posix/sigintr.c
* sysdeps/posix/signal.c, sysdeps/posix/sigset.c
* sysdeps/posix/sprofil.c, sysdeps/posix/sysv_signal.c
* sysdeps/unix/sysv/linux/nptl-signals.h:
Include sigsetops.h.
* signal/sigaddset.c, signal/sigandset.c, signal/sigdelset.c
* signal/sigorset.c, stdlib/abort.c, sysdeps/posix/sigignore.c
* sysdeps/posix/signal.c, sysdeps/posix/sigset.c:
__sigaddset, __sigandset, __sigdelset, __sigemptyset, __sigorset
now return no value.
* signal/sigaddset.c, signal/sigdelset.c, signal/sigismem.c
Include <errno.h>, <signal.h>, and <sigsetops.h> instead of
"sigsetops.h".
* signal/sigsetops.c: Explicitly define __sigismember,
__sigaddset, and __sigdelset as compatibility symbols.
* signal/Versions: Correct commentary on __sigpause,
__sigaddset, __sigdelset, __sigismember.
* inet/rcmd.c: Include sigsetops.h. Convert old code using
__sigblock/__sigsetmask to use __sigprocmask and friends.
This patch consolidates the mq_timedsend Linux syscall generation
on sysdeps/unix/sysv/linux/mq_timedsend.c. It basically removes it
from architecture auto-generation list.
Checked on i686-linux-gnu, x86_64-linux-gnu, x86_64-linux-gnux32,
arch64-linux-gnu, arm-linux-gnueabihf, powerpc64le-linux-gnu,
sparc64-linux-gnu, and sparcv9-linux-gnu.
* rt/Makefile (CFLAGS-mq_timedsend.c): New flag.
* sysdeps/unix/sysv/linux/mq_timedsend.c: New file.
* sysdeps/unix/sysv/linux/syscalls.list (mq_timedsend): Remove from
auto-generation list.
This patch consolidates the mq_timedreceive Linux syscall generation
on sysdeps/unix/sysv/linux/mq_timedreceive.c. It basically removes it
from architecture auto-generation list.
Checked on i686-linux-gnu, x86_64-linux-gnu, x86_64-linux-gnux32,
arch64-linux-gnu, arm-linux-gnueabihf, powerpc64le-linux-gnu,
sparc64-linux-gnu, and sparcv9-linux-gnu.
* rt/Makefile (CFLAGS-mq_timedreceive.c): New flag.
* sysdeps/unix/sysv/linux/mq_timedreceive.c: New file.
* sysdeps/unix/sysv/linux/syscalls.list (mq_timedreceive): Remove
from auto-generation list.
The new test driver in <support/test-driver.c> has feature parity with
the old one. The main difference is that its hooking mechanism is
based on functions and function pointers instead of macros. This
commit also implements a new environment variable, TEST_COREDUMPS,
which disables the code which disables coredumps (that is, it enables
them if the invocation environment has not disabled them).
<test-skeleton.c> defines wrapper functions so that it is possible to
use existing macros with the new-style hook functionality.
This commit changes only a few test cases to the new test driver, to
make sure that it works as expected.
This patch uses the libc_ifunc macro to create already existing ifunc functions
clock_getres, clock_gettime, clock_settime, clock_getcpuclockid and
clock_nanosleep. If HAVE_IFUNC is defined, the macro COMPAT_REDIRECT uses
the libc_ifunc macro.
Furthermore some whitespace damage is cleaned.
ChangeLog:
* rt/clock-compat.c (COMPAT_REDIRECT): Use libc_ifunc macro.
Many headers are expected to expose a subset of the type definitions
in time.h. time.h has a whole bunch of messy logic for conditionally
defining some its types and structs, but, as best I can tell, this
has never worked 100%. In particular, __need_timespec is ineffective
if _TIME_H has already been defined, which means that if you compile
#include <time.h>
#include <sched.h>
with e.g. -fsyntax-only -std=c89 -Wall -Wsystem-headers, you will get
In file included from test.c:2:0:
/usr/include/sched.h:74:57: warning: "struct timespec" declared inside
parameter list will not be visible outside of this definition or declaration
extern int sched_rr_get_interval (__pid_t __pid, struct timespec *__t) __THROW;
^~~~~~~~
And if you want to _use_ sched_rr_get_interval in a TU compiled that
way, you're hosed.
This patch replaces all of that with small bits/types/TYPE.h headers
as introduced earlier. time.h and bits/time.h are now *much* simpler,
and a lot of other headers are slightly simpler.
* time/time.h, bits/time.h, sysdeps/unix/sysv/linux/bits/time.h:
Remove all logic conditional on __need macros. Move all the
conditionally defined types to their own headers...
* time/bits/types/clock_t.h: Define clock_t here.
* time/bits/types/clockid_t.h: Define clockid_t here.
* time/bits/types/struct_itimerspec.h: Define struct itimerspec here.
* time/bits/types/struct_timespec.h: Define struct timespec here.
* time/bits/types/struct_timeval.h: Define struct timeval here.
* time/bits/types/struct_tm.h: Define struct tm here.
* time/bits/types/time_t.h: Define time_t here.
* time/bits/types/timer_t.h: Define timer_t here.
* time/Makefile: Install the new headers.
* bits/resource.h, io/fcntl.h, io/sys/poll.h, io/sys/stat.h
* io/utime.h, misc/sys/select.h, posix/sched.h, posix/sys/times.h
* posix/sys/types.h, resolv/netdb.h, rt/aio.h, rt/mqueue.h
* signal/signal.h, pthread/semaphore.h, sysdeps/nptl/pthread.h
* sysdeps/unix/sysv/linux/alpha/bits/resource.h
* sysdeps/unix/sysv/linux/alpha/sys/acct.h
* sysdeps/unix/sysv/linux/bits/resource.h
* sysdeps/unix/sysv/linux/bits/timex.h
* sysdeps/unix/sysv/linux/mips/bits/resource.h
* sysdeps/unix/sysv/linux/net/ppp_defs.h
* sysdeps/unix/sysv/linux/sparc/bits/resource.h
* sysdeps/unix/sysv/linux/sys/acct.h
* sysdeps/unix/sysv/linux/sys/timerfd.h
* sysvipc/sys/msg.h, sysvipc/sys/sem.h, sysvipc/sys/shm.h
* time/sys/time.h, time/sys/timeb.h
Use the new bits/types headers.
* include/time.h: Remove __need logic.
* include/bits/time.h
* include/bits/types/clock_t.h, include/bits/types/clockid_t.h
* include/bits/types/time_t.h, include/bits/types/timer_t.h
* include/bits/types/struct_itimerspec.h
* include/bits/types/struct_timespec.h
* include/bits/types/struct_timeval.h
* include/bits/types/struct_tm.h:
New wrapper headers.
This patch changes shm_open to not act as a cancellation point.
Cancellation is disable at start and reenable in function exit.
It fixes BZ #18243.
Tested on x86_64 and i686.
[BZ #18243]
* rt/Makefile (test): Add tst-shm-cancel.
* rt/tst-shm-cancel.c: New file.
* sysdeps/posix/shm_open.c: Disable asynchronous cancellation.
The check is done on line 117 by a thread spawned
from do_child(), forked from do_test(). This test
generates a signal in the forked process.
Either thread may handle the signal, and on ppc,
it happens to be done on do_child, on the thread
which is not doing the check on line 117.
This exposes a race condition whereby the test
incorrectly fails as the signal is caught during
or after the check.
This is mitigated by ensuring the signal is blocked
in the child thread while thread is running.
I noticed that glibc testsuite runs left several files behind in /tmp
(or TMPDIR, if different). The problem was testcases that generate a
template for mkstemp / mkstemp64, ending with XXXXXX, then pass that
template to add_temp_file before calling mkstemp / mkstemp64, meaning
that the template ending with XXXXXX is stored in the list of
temporary files to delete (add_temp_file uses strdup so that the
original string doesn't need to stay live), not the actual filename as
determined by mkstemp / mkstemp64. This patch fixes those tests to
call add_temp_file later.
Tested for x86_64 (that the files are no longer left behind by a
testsuite run and the modified tests still pass).
* io/test-lfs.c (do_prepare): Do not call add_temp_file until
after mkstemp64.
* login/tst-utmp.c (do_prepare): Likewise.
* rt/tst-aio.c (do_prepare): Likewise.
* rt/tst-aio64.c (do_prepare): Likewise.
mq_receive calls mq_timedreceive, and mq_send calls mq_timedsend. But
mq_receive and mq_send were in POSIX by 1996, while mq_timed* were
added in the 2001 edition of POSIX. This patch fixes this by making
mq_timed* into weak aliases for __mq_timed* and calling the
__mq_timed* names.
Tested for x86_64 and x86 (testsuite, and that disassembly of
installed shared libraries is unchanged by the patch).
[BZ #18545]
* rt/mq_timedreceive.c (mq_timedreceive): Rename to
__mq_timedreceive and define as alias of __mq_timedreceive. Use
hidden_weak.
* rt/mq_timedsend.c (mq_timedsend): Rename to __mq_timedsend and
define as alias of __mq_timedsend. Use hidden_weak.
* sysdeps/unix/sysv/linux/syscalls.list (mq_timedsend): Use
__mq_timedsend as strong name.
(mq_timedreceive): Use __mq_timedreceive as strong name.
* include/mqueue.h (__mq_timedsend): Declare. Use hidden_proto.
(__mq_timedreceive): Likewise.
* sysdeps/unix/sysv/linux/mq_receive.c (mq_receive): Call
__mq_timedreceive instead of mq_timedreceive.
* sysdeps/unix/sysv/linux/mq_send.c (mq_send): Call __mq_timedsend
instead of mq_timedsend.
* conform/Makefile (test-xfail-UNIX98/mqueue.h/linknamespace):
Remove variable.
I noticed that some of the Depend files, used to determine the
subdirectory build order in sysd-sorted, still mentioned linuxthreads,
although it hasn't been supported for many years. This patch removes
those references. In the case of nscd, it substitutes an nptl
reference, since I believe there is a fact a thread library dependence
there; the others already mentioned nptl.
Note that I am not at all confident in the completeness of these
Depend files.
Note also that references to linuxthreads remain in a comment in
sysdeps/unix/sysv/linux/ia64/Versions, and in manual/maint.texi,
manual/signal.texi and scripts/documented.sh.
Tested x86_64 that the installed shared libraries are unchanged by the
patch (as is sysd-sorted).
* nscd/Depend (linuxthreads): Remove.
(nptl): Add.
* resolv/Depend (linuxthreads): Remove.
* rt/Depend (linuxthreads): Remove.
In <https://sourceware.org/ml/libc-alpha/2014-01/msg00196.html> I
noted it was necessary to add includes of Makeconfig early in various
subdirectory makefiles for the tests-special variable settings added
by that patch to be conditional on configuration information. No-one
commented on the general question there of whether Makeconfig should
always be included immediately after the definition of subdir.
This patch implements that early inclusion of Makeconfig in each
directory (which is a lot easier than consistent placement of includes
of Rules). Includes are added if needed, or moved up if already
present. Subdirectory "all:" targets are removed, since Makeconfig
provides one.
There is potential for further cleanups I haven't done. Rules and
Makerules have code such as
ifneq "$(findstring env,$(origin headers))" ""
headers :=
endif
to override to empty any value of various variables that came from the
environment. I think there is a case for Makeconfig setting all the
subdirectory variables (other than subdir) to empty to ensure no
outside value is going to take effect if a subdirectory fails to
define a variable. (A list of such variables, possibly out of date
and incomplete, is in manual/maint.texi.) Rules and Makerules would
give errors if Makeconfig hadn't already been included, instead of
including it themselves. The special code to override values coming
from the environment would then be obsolete and could be removed.
Tested x86_64, including that installed binaries are identical before
and after the patch.
* argp/Makefile: Include Makeconfig immediately after defining
subdir.
* assert/Makefile: Likewise.
* benchtests/Makefile: Likewise.
* catgets/Makefile: Likewise.
* conform/Makefile: Likewise.
* crypt/Makefile: Likewise.
* csu/Makefile: Likewise.
(all): Remove target.
* ctype/Makefile: Include Makeconfig immediately after defining
subdir.
* debug/Makefile: Likewise.
* dirent/Makefile: Likewise.
* dlfcn/Makefile: Likewise.
* gmon/Makefile: Likewise.
* gnulib/Makefile: Likewise.
* grp/Makefile: Likewise.
* gshadow/Makefile: Likewise.
* hesiod/Makefile: Likewise.
* hurd/Makefile: Likewise.
(all): Remove target.
* iconvdata/Makefile: Include Makeconfig immediately after
defining subdir.
* inet/Makefile: Likewise.
* intl/Makefile: Likewise.
* io/Makefile: Likewise.
* libio/Makefile: Likewise.
(all): Remove target.
* locale/Makefile: Include Makeconfig immediately after defining
subdir.
* login/Makefile: Likewise.
* mach/Makefile: Likewise.
(all): Remove target.
* malloc/Makefile: Include Makeconfig immediately after defining
subdir.
(all): Remove target.
* manual/Makefile: Include Makeconfig immediately after defining
subdir.
* math/Makefile: Likewise.
* misc/Makefile: Likewise.
* nis/Makefile: Likewise.
* nss/Makefile: Likewise.
* po/Makefile: Likewise.
(all): Remove target.
* posix/Makefile: Include Makeconfig immediately after defining
subdir.
* pwd/Makefile: Likewise.
* resolv/Makefile: Likewise.
* resource/Makefile: Likewise.
* rt/Makefile: Likewise.
* setjmp/Makefile: Likewise.
* shadow/Makefile: Likewise.
* signal/Makefile: Likewise.
* socket/Makefile: Likewise.
* soft-fp/Makefile: Likewise.
* stdio-common/Makefile: Likewise.
* stdlib/Makefile: Likewise.
* streams/Makefile: Likewise.
* string/Makefile: Likewise.
* sunrpc/Makefile: Likewise.
(all): Remove target.
* sysvipc/Makefile: Include Makeconfig immediately after defining
subdir.
* termios/Makefile: Likewise.
* time/Makefile: Likewise.
* timezone/Makefile: Likewise.
(all): Remove target.
* wcsmbs/Makefile: Include Makeconfig immediately after defining
subdir.
* wctype/Makefile: Likewise.
libidn/ChangeLog:
* Makefile: Include Makeconfig immediately after defining subdir.
localedata/ChangeLog:
* Makefile: Include Makeconfig immediately after defining subdir.
(all): Remove target.
nptl/ChangeLog:
* Makefile: Include Makeconfig immediately after defining subdir.
nptl_db/ChangeLog:
* Makefile: Include Makeconfig immediately after defining subdir.
__clock_gettime and other __clock_* functions could result in an extra
PLT reference within libc.so if it actually gets used. None of the
code currently uses them, which is why this probably went unnoticed.
