diff --git a/ChangeLog b/ChangeLog
index 2b901c02e3..96a9bdaeca 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,13 @@
+1998-06-18 21:45  Ulrich Drepper  <drepper@cygnus.com>
+
+	* signal/signal.h: Add prototype for __sigaltstack.
+	* sysdeps/unix/sysv/linux/syscalls.list: Add __sigaltstack name.
+	Remove sigstack entry.
+	* sysdeps/unix/sysv/linux/alpha/syscalls.list: Add sigstack here.
+	* sysdeps/unix/sysv/linux/sigstack.c: New file.
+
+	* sysdeps/i386/backtrace.c: Add casts.
+
 1998-06-18 19:49  Ulrich Drepper  <drepper@cygnus.com>
 
 	* intl/dcgettext.c: use complete type name.
diff --git a/signal/signal.h b/signal/signal.h
index b42d897f8b..aa51593b67 100644
--- a/signal/signal.h
+++ b/signal/signal.h
@@ -328,6 +328,8 @@ extern int sigstack __P ((__const struct sigstack *__ss,
 
 /* Alternate signal handler stack interface.
    This interface should always be preferred over `sigstack'.  */
+extern int __sigaltstack __P ((__const struct sigaltstack *__ss,
+			       struct sigaltstack *__oss));
 extern int sigaltstack __P ((__const struct sigaltstack *__ss,
 			     struct sigaltstack *__oss));
 
diff --git a/sysdeps/i386/backtrace.c b/sysdeps/i386/backtrace.c
index 5e84205b04..38635988f4 100644
--- a/sysdeps/i386/backtrace.c
+++ b/sysdeps/i386/backtrace.c
@@ -55,7 +55,7 @@ __backtrace (array, size)
   current = (struct layout *) ebp;
   while (cnt < size)
     {
-      if (current < esp || current > __libc_stack_end)
+      if ((void *) current < esp || (void *) current > __libc_stack_end)
 	/* This means the address is out of range.  Note that for the
 	   toplevel we see a frame pointer with value NULL which clearly is
 	   out of range.  */
diff --git a/sysdeps/unix/sysv/linux/alpha/syscalls.list b/sysdeps/unix/sysv/linux/alpha/syscalls.list
index 0b38038d46..ff73a6dc9f 100644
--- a/sysdeps/unix/sysv/linux/alpha/syscalls.list
+++ b/sysdeps/unix/sysv/linux/alpha/syscalls.list
@@ -16,6 +16,7 @@ semget		-	semget		3	__semget	semget
 semctl		-	semctl		4	__semctl	semctl
 
 osf_sigprocmask	-	osf_sigprocmask	2	__osf_sigprocmask
+sigstack	-	sigstack	2	sigstack
 
 getpeername	-	getpeername	3	__getpeername	getpeername
 getpriority	-	getpriority	2	__getpriority	getpriority
diff --git a/sysdeps/unix/sysv/linux/sigstack.c b/sysdeps/unix/sysv/linux/sigstack.c
new file mode 100644
index 0000000000..bca7dc634e
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/sigstack.c
@@ -0,0 +1,61 @@
+/* Emulate sigstack function using sigalstack.
+   Copyright (C) 1998 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Ulrich Drepper <drepper@cygnus.com>, 1998.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 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
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#include <signal.h>
+
+
+int
+sigstack (ss, oss)
+     const struct sigstack *ss;
+     struct sigstack *oss;
+{
+  stack_t sas;
+  stack_t *sasp = NULL;
+  stack_t osas;
+  stack_t *osasp = oss == NULL ? NULL : &osas;
+  int result;
+
+  if (ss != NULL)
+    {
+      /* We have to convert the information.  */
+      sas.ss_sp = ss->ss_sp;
+      sas.ss_flags = ss->ss_onstack ? SS_ONSTACK : 0;
+
+      /* For the size of the stack we have no value we can pass to the
+	 kernel.  This is why this function should not be used.  We simply
+	 assume that all the memory down to address zero (in case the stack
+	 grows down) is available.  */
+      sas.ss_size = ss->ss_sp - NULL;
+
+      sasp = &sas;
+    }
+
+  /* Call the kernel.  */
+  result = __sigaltstack (sasp, osasp);
+
+  /* Convert the result, if wanted and possible.  */
+  if (result == 0 && oss != NULL)
+    {
+      oss->ss_sp = osas.ss_sp;
+      oss->ss_onstack = (osas.ss_flags & SS_ONSTACK) != 0;
+    }
+
+  return result;
+}
diff --git a/sysdeps/unix/sysv/linux/syscalls.list b/sysdeps/unix/sysv/linux/syscalls.list
index 739e29c536..e80fd84568 100644
--- a/sysdeps/unix/sysv/linux/syscalls.list
+++ b/sysdeps/unix/sysv/linux/syscalls.list
@@ -72,8 +72,7 @@ setfsuid	EXTRA	setfsuid	1	setfsuid
 setpgid		-	setpgid		2	__setpgid	setpgid
 setresgid	EXTRA	setresgid	3	setresgid
 setresuid	EXTRA	setresuid	3	setresuid
-sigaltstack	-	sigaltstack	2	sigaltstack
-sigstack	-	sigstack	2	sigstack
+sigaltstack	-	sigaltstack	2	__sigaltstack	sigaltstack
 sys_fstat	fxstat	fstat		2	__syscall_fstat
 sys_lstat	lxstat	lstat		2	__syscall_lstat
 sys_mknod	xmknod	mknod		3	__syscall_mknod