It now calls __libc_assert, which contains similar logic. The assert
call only requires memory allocation for the message translation, so
test-assert2.c is adapted to handle it.

It also removes the fxprintf from assert/assert_perror; although it
is not 100% backwards-compatible (write message only if there is a
file descriptor associated with the stderr). It now writes bytes
directly without going through the wide stream state.

Checked on aarch64-linux-gnu.

Reviewed-by: Florian Weimer <fweimer@redhat.com>

Include the space needed to store the length of the message itself, in
addition to the message string.  This resolves BZ #32582.

Signed-off-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
Reviewed: Adhemerval Zanella  <adhemerval.zanella@linaro.org>

The require size for mmap can be inferred from __vasprintf return
value.  It also fixes tst-assert-2 when building with --enable-fortify,
where even if the format is not translated, __readonly_area fails
because malloc can not be used.

Checked on aarch64-linux-gnu.

Reviewed-by: Florian Weimer <fweimer@redhat.com>

Replace writev with __writev in assert/assert.c.  This fixes [BZ #32492].

Reviewed-by: H.J. Lu <hjl.tools@gmail.com>

Fix assert.c so that even the fallback
case conforms to POSIX, although not exactly the same as
the default case so a test can tell the difference.

Add a test that verifies that abort is called, and that the
message printed to stderr has all the info that POSIX requires.
Verify this even when malloc isn't usable.

Reviewed-by: Paul Eggert <eggert@cs.ucla.edu>

Reviewed-by: DJ Delorie <dj@redhat.com>

Rename atomic_exchange_rel/acq to use atomic_exchange_release/acquire
since these map to the standard C11 atomic builtins.

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