nptl: Move __pthread_unwind_next into libc

It's necessary to stub out __libc_disable_asynccancel and
__libc_enable_asynccancel via rtld-stubbed-symbols because the new
direct references to the unwinder result in symbol conflicts when the
rtld exception handling from libc is linked in during the construction
of librtld.map.

unwind-forcedunwind.c is merged into unwind-resume.c.  libc now needs
the functions that were previously only used in libpthread.

The GLIBC_PRIVATE exports of __libc_longjmp and __libc_siglongjmp are
no longer needed, so switch them to hidden symbols.

The symbol __pthread_unwind_next has been moved using
scripts/move-symbol-to-libc.py.

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

71 files changed, 86 insertions, 162 deletions

diff --git a/sysdeps/arm/Makefile b/sysdeps/arm/Makefile
index ad2042b93a..fb4164f0d9 100644
--- a/sysdeps/arm/Makefile
+++ b/sysdeps/arm/Makefile
@@ -63,8 +63,3 @@ ifeq ($(subdir),rt)
 librt-sysdep_routines += rt-aeabi_unwind_cpp_pr1 rt-arm-unwind-resume
 librt-shared-only-routines += rt-aeabi_unwind_cpp_pr1 rt-arm-unwind-resume
 endif
-
-ifeq ($(subdir),nptl)
-libpthread-sysdep_routines += pt-arm-unwind-resume
-libpthread-shared-only-routines += pt-arm-unwind-resume
-endif
diff --git a/sysdeps/arm/nptl/unwind-forcedunwind.c b/sysdeps/arm/nptl/unwind-forcedunwind.c
deleted file mode 100644
index 61db34c0b5..0000000000
--- a/sysdeps/arm/nptl/unwind-forcedunwind.c
+++ /dev/null
@@ -1,25 +0,0 @@
-/* Unwinder function forwarders for libpthread.  Arm version.
-   Copyright (C) 2021 Free Software Foundation, Inc.
-   This file is part of the GNU C Library.
-
-   The GNU C Library is free software; you can redistribute it and/or
-   modify it under the terms of the GNU Lesser General Public License as
-   published by the Free Software Foundation; either version 2.1 of the
-   License, or (at your option) any later version.
-
-   The GNU C Library is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-   Lesser General Public License for more details.
-
-   You should have received a copy of the GNU Lesser General Public
-   License along with the GNU C Library; see the file COPYING.LIB.  If
-   not, see <https://www.gnu.org/licenses/>.  */
-
-#include <sysdeps/nptl/unwind-forcedunwind.c>
-
-void *
-__unwind_link_get_resume (void)
-{
-  return UNWIND_LINK_PTR (__pthread_unwind_link_get (), _Unwind_Resume);
-}
diff --git a/sysdeps/arm/pt-arm-unwind-resume.S b/sysdeps/arm/pt-arm-unwind-resume.S
deleted file mode 100644
index c056eb38d0..0000000000
--- a/sysdeps/arm/pt-arm-unwind-resume.S
+++ /dev/null
@@ -1,20 +0,0 @@
-/* _Unwind_Resume wrapper for ARM EABI.
-   Copyright (C) 2015-2021 Free Software Foundation, Inc.
-   This file is part of the GNU C Library.
-
-   The GNU C Library is free software; you can redistribute it and/or
-   modify it under the terms of the GNU Lesser General Public License as
-   published by the Free Software Foundation; either version 2.1 of the
-   License, or (at your option) any later version.
-
-   The GNU C Library is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-   Lesser General Public License for more details.
-
-   You should have received a copy of the GNU Lesser General Public
-   License along with the GNU C Library.  If not, see
-   <https://www.gnu.org/licenses/>.  */
-
-/* The implementation in libpthread is identical to the one in libc.  */
-#include <sysdeps/arm/arm-unwind-resume.S>
diff --git a/sysdeps/generic/unwind-resume.c b/sysdeps/generic/unwind-resume.c
index 9e63762bf1..66dbb67e81 100644
--- a/sysdeps/generic/unwind-resume.c
+++ b/sysdeps/generic/unwind-resume.c
@@ -44,3 +44,17 @@ __gcc_personality_v0 PERSONALITY_PROTO
 {
   return UNWIND_LINK_PTR (link (), personality) PERSONALITY_ARGS;
 }
+
+_Unwind_Reason_Code
+_Unwind_ForcedUnwind (struct _Unwind_Exception *exc, _Unwind_Stop_Fn stop,
+                      void *stop_argument)
+{
+  return UNWIND_LINK_PTR (link (), _Unwind_ForcedUnwind)
+    (exc, stop, stop_argument);
+}
+
+_Unwind_Word
+_Unwind_GetCFA (struct _Unwind_Context *context)
+{
+  return UNWIND_LINK_PTR (link (), _Unwind_GetCFA) (context);
+}
diff --git a/sysdeps/unix/sysv/linux/ia64/unwind-forcedunwind.c b/sysdeps/ia64/unwind-resume.c
index eaed6cf2ef..f8cf447162 100644
--- a/sysdeps/unix/sysv/linux/ia64/unwind-forcedunwind.c
+++ b/