Fix getpass fflush_unlocked namespace (bug 18540).
The getpass function (XPG3 / XPG4 / UNIX98) calls fflush_unlocked (not
in any of those standards). This patch fixes this by making
fflush_unlocked into a weak alias for __fflush_unlocked and calling
__fflush_unlocked from getpass.
Tested for x86_64 and x86 (testsuite, and that disassembly of
installed stripped shared libraries is unchanged by the patch).
[BZ #18540]
* libio/iofflush.c [!_IO_MTSAFE_IO] (__fflush_unlocked): Define as
strong alias of _IO_fflush. Use libc_hidden_def.
* libio/iofflush_u.c (fflush_unlocked): Rename to
__fflush_unlocked and define as weak alias of __fflush_unlocked.
Use libc_hidden_weak.
* include/stdio.h (__fflush_unlocked): Declare. Use
libc_hidden_proto.
* misc/getpass.c (getpass): Call __fflush_unlocked instead of
fflush_unlocked.
* conform/Makefile (test-xfail-UNIX98/unistd.h/linknamespace):
Remove variable.