or1k: Add prctl wrapper to unwrap variadic args

On OpenRISC variadic functions and regular functions have different
calling conventions so this wrapper is needed to translate.  This
wrapper is copied from x86_64/x32.  I don't know the build system enough
to find a cleaner way to share the code between x86_64/x32 and or1k
(maybe Implies?), so I went with the straight copy.

This fixes test failures:

  misc/tst-prctl
  nptl/tst-setgetname

diff --git a/sysdeps/unix/sysv/linux/or1k/prctl.c b/sysdeps/unix/sysv/linux/or1k/prctl.c
new file mode 100644 (file)
index 0000000..1aa707d
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/or1k/prctl.c
@@ -0,0 +1,42 @@
+/* prctl - Linux specific syscall.  OpenRISC version.
+   Copyright (C) 2024 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/>.  */
+
+#include <sysdep.h>
+#include <stdarg.h>
+#include <sys/prctl.h>
+
+/* Unconditionally read all potential arguments.  This may pass
+   garbage values to the kernel, but avoids the need for teaching
+   glibc the argument counts of individual options (including ones
+   that are added to the kernel in the future).  */
+
+int
+__prctl (int option, ...)
+{
+  va_list arg;
+  va_start (arg, option);
+  unsigned long int arg2 = va_arg (arg, unsigned long int);
+  unsigned long int arg3 = va_arg (arg, unsigned long int);
+  unsigned long int arg4 = va_arg (arg, unsigned long int);
+  unsigned long int arg5 = va_arg (arg, unsigned long int);
+  va_end (arg);
+  return INLINE_SYSCALL_CALL (prctl, option, arg2, arg3, arg4, arg5);
+}
+
+libc_hidden_def (__prctl)
+weak_alias (__prctl, prctl)