Test that clock_nanosleep rejects out of range time values.

Test that clock_nanosleep actually sleeps for at least the
requested time relative to the requested clock.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>

Since the _FORTIFY_SOURCE feature uses some routines of Glibc, they need to
be excluded from the fortification.

On top of that:
 - some tests explicitly verify that some level of fortification works
   appropriately, we therefore shouldn't modify the level set for them.
 - some objects need to be build with optimization disabled, which
   prevents _FORTIFY_SOURCE to be used for them.

Assembler files that implement architecture specific versions of the
fortified routines were not excluded from _FORTIFY_SOURCE as there is no
C header included that would impact their behavior.

Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>

I used these shell commands:

../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright
(cd ../glibc && git commit -am"[this commit message]")

and then ignored the output, which consisted lines saying "FOO: warning:
copyright statement not found" for each of 7061 files FOO.

I then removed trailing white space from math/tgmath.h,
support/tst-support-open-dev-null-range.c, and
sysdeps/x86_64/multiarch/strlen-vec.S, to work around the following
obscure pre-commit check failure diagnostics from Savannah.  I don't
know why I run into these diagnostics whereas others evidently do not.

remote: *** 912-#endif
remote: *** 913:
remote: *** 914-
remote: *** error: lines with trailing whitespace found
...
remote: *** error: sysdeps/unix/sysv/linux/statx_cp.c: trailing lines

This test implements following logic:
1) Create POSIX message queue.
   Register a notification with mq_notify (using NULL attributes).
   Then immediately unregister the notification with mq_notify.
   Helper thread in a vulnerable version of glibc
   should cause NULL pointer dereference after these steps.
2) Once again, register the same notification.
   Try to send a dummy message.
   Test is considered successfulif the dummy message
   is successfully received by the callback function.

Signed-off-by: Nikita Popov <npv1310@gmail.com>
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>

librt.so is no longer installed for PTHREAD_IN_LIBC, and tests
are not linked against it.  $(librt) is introduced globally for
shared tests that need to be linked for both PTHREAD_IN_LIBC
and !PTHREAD_IN_LIBC.

GLIBC_PRIVATE symbols that were needed during the transition are
removed again.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>

The symbols were moved using scripts/move-symbol-to-libc.py.

The way the ABI intransition is implemented is changed with this
commit: the implementation is now consolidated in one file with a
TIMER_T_WAS_INT_COMPAT check.

The shared librt is now empty, so this commit adds a placeholder
symbol at the base version, GLIBC_2.2, and potentially at the
GLIBC_2.3.3 version as well (the leftover from the int/timer_t ABI
transition).

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>

The symbols were moved using scripts/move-symbol-to-libc.py.

The way the ABI intransition is implemented is changed with this
commit: the implementation is now consolidated in one file with a
TIMER_T_WAS_INT_COMPAT check.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>