Split up bits/sigstack.h.

bits/sigstack.h contains four things: the legacy struct sigstack type,
the preferred stack_t type, the SS_* enum values and macros for signal
stack sizes.

These vary in different ways between glibc configurations; in
particular, the stack sizes vary much more than any of the other
pieces.  Furthermore, these pieces have different standard namespace
rules for when they should be visible (not currently visible in
conform/ results both because the relevant tests are XFAILed for
sys/ucontext.h namespace issues, and because some of the expectations
are incorrect in the same way as the headers, e.g. neither
expectations nor headers reflect that current POSIX no longer has
either the sigstack function or the sigstack structure).

To reduce duplication of identical definitions, and facilitate
namespace fixes without requiring the same feature test macro
conditions to be repeated in many versions of the same header, this
patch splits bits/sigstack.h up into four headers.  It keeps the stack
size macros, while new bits/types/struct_sigstack.h,
bits/types/stack_t.h and bits/ss_flags.h are added for the other
pieces.  bits/types/struct_sigstack.h is the same everywhere,
bits/types/stack_t.h has three variants different in the order of the
structure elements (generic = MIPS Linux, and other Linux), and
bits/ss_flags.h has generic and Linux variants.

This patch includes the new headers everywhere that included
<bits/sigstack.h>, so should cause no difference to what any public
header defines.  Subsequent namespace fixes would then remove or
condition some of those includes.

There should be no conflicts with Zack's changes to signal.h types,
beyond the trivial conflict of both making additions to
signal/Makefile's headers list; the two patches affect disjoint sets
of types and other definitions.

Tested for x86_64 and x86, and with build-many-glibcs.py.

	* bits/ss_flags.h: New file.
	* bits/types/stack_t.h: Likewise.
	* include/bits/types/struct_sigstack.h: Likewise.
	* signal/bits/types/struct_sigstack.h: Likewise.
	* sysdeps/unix/sysv/linux/bits/ss_flags.h: Likewise.
	* sysdeps/unix/sysv/linux/bits/types/stack_t.h: Likewise.
	* sysdeps/unix/sysv/linux/mips/bits/types/stack_t.h: Likewise.
	* signal/Makefile (headers): Add bits/types/struct_sigstack.h,
	bits/types/stack_t.h and bits/ss_flags.h.
	* signal/signal.h [__USE_XOPEN_EXTENDED || __USE_XOPEN2K8]:
	Include <bits/types/struct_sigstack.h>, <bits/types/stack_t.h> and
	<bits/ss_flags.h>.
	* bits/sigstack.h (struct sigstack): Remove.
	(stack_t): Likewise.
	(SS_ONSTACK): Likewise.
	(SS_DISABLE): Likewise.
	* sysdeps/unix/sysv/linux/aarch64/bits/sigstack.h
	(struct sigstack): Likewise.
	(stack_t): Likewise.
	(SS_ONSTACK): Likewise.
	(SS_DISABLE): Likewise.
	* sysdeps/unix/sysv/linux/alpha/bits/sigstack.h (struct sigstack):
	Likewise.
	(stack_t): Likewise.
	(SS_ONSTACK): Likewise.
	(SS_DISABLE): Likewise.
	* sysdeps/unix/sysv/linux/bits/sigstack.h (struct sigstack):
	Likewise.
	(stack_t): Likewise.
	(SS_ONSTACK): Likewise.
	(SS_DISABLE): Likewise.
	* sysdeps/unix/sysv/linux/mips/bits/sigstack.h: Likewise.
	* sysdeps/unix/sysv/linux/ia64/bits/sigstack.h (struct sigstack):
	Likewise.
	(stack_t): Likewise.
	(SS_ONSTACK): Likewise.
	(SS_DISABLE): Likewise.
	* sysdeps/unix/sysv/linux/powerpc/bits/sigstack.h
	(struct sigstack): Likewise.
	(stack_t): Likewise.
	(SS_ONSTACK): Likewise.
	(SS_DISABLE): Likewise.
	* sysdeps/unix/sysv/linux/sparc/bits/sigstack.h (struct sigstack):
	Likewise.
	(stack_t): Likewise.
	(SS_ONSTACK): Likewise.
	(SS_DISABLE): Likewise.
	* sysdeps/arm/sys/ucontext.h: Include
	<bits/types/struct_sigstack.h>, <bits/types/stack_t.h> and
	<bits/ss_flags.h>.
	* sysdeps/generic/sys/ucontext.h: Likewise.
	* sysdeps/i386/sys/ucontext.h: Likewise.
	* sysdeps/m68k/sys/ucontext.h: Likewise.
	* sysdeps/mips/sys/ucontext.h: Likewise.
	* sysdeps/unix/sysv/linux/aarch64/sys/ucontext.h: Likewise.
	* sysdeps/unix/sysv/linux/alpha/sys/ucontext.h: Likewise.
	* sysdeps/unix/sysv/linux/arm/sys/ucontext.h: Likewise.
	* sysdeps/unix/sysv/linux/hppa/sys/ucontext.h: Likewise.
	* sysdeps/unix/sysv/linux/ia64/bits/sigcontext.h: Likewise.
	* sysdeps/unix/sysv/linux/ia64/sys/ucontext.h: Likewise.
	* sysdeps/unix/sysv/linux/m68k/sys/ucontext.h: Likewise.
	* sysdeps/unix/sysv/linux/mips/sys/ucontext.h: Likewise.
	* sysdeps/unix/sysv/linux/nios2/sys/ucontext.h: Likewise.
	* sysdeps/unix/sysv/linux/powerpc/sys/ucontext.h: Likewise.
	* sysdeps/unix/sysv/linux/s390/sys/ucontext.h: Likewise.
	* sysdeps/unix/sysv/linux/sh/sys/ucontext.h: Likewise.
	* sysdeps/unix/sysv/linux/sparc/sys/ucontext.h: Likewise.
	* sysdeps/unix/sysv/linux/tile/sys/ucontext.h: Likewise.
	* sysdeps/unix/sysv/linux/x86/sys/ucontext.h: Likewise.

37 files changed, 306 insertions, 219 deletions

diff --git a/ChangeLog b/ChangeLog
index b9fbdb8351..f25eb14ca9 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,75 @@
+2017-05-19  Joseph Myers  <joseph@codesourcery.com>
+
+	* bits/ss_flags.h: New file.
+	* bits/types/stack_t.h: Likewise.
+	* include/bits/types/struct_sigstack.h: Likewise.
+	* signal/bits/types/struct_sigstack.h: Likewise.
+	* sysdeps/unix/sysv/linux/bits/ss_flags.h: Likewise.
+	* sysdeps/unix/sysv/linux/bits/types/stack_t.h: Likewise.
+	* sysdeps/unix/sysv/linux/mips/bits/types/stack_t.h: Likewise.
+	* signal/Makefile (headers): Add bits/types/struct_sigstack.h,
+	bits/types/stack_t.h and bits/ss_flags.h.
+	* signal/signal.h [__USE_XOPEN_EXTENDED || __USE_XOPEN2K8]:
+	Include <bits/types/struct_sigstack.h>, <bits/types/stack_t.h> and
+	<bits/ss_flags.h>.
+	* bits/sigstack.h (struct sigstack): Remove.
+	(stack_t): Likewise.
+	(SS_ONSTACK): Likewise.
+	(SS_DISABLE): Likewise.
+	* sysdeps/unix/sysv/linux/aarch64/bits/sigstack.h
+	(struct sigstack): Likewise.
+	(stack_t): Likewise.
+	(SS_ONSTACK): Likewise.
+	(SS_DISABLE): Likewise.
+	* sysdeps/unix/sysv/linux/alpha/bits/sigstack.h (struct sigstack):
+	Likewise.
+	(stack_t): Likewise.
+	(SS_ONSTACK): Likewise.
+	(SS_DISABLE): Likewise.
+	* sysdeps/unix/sysv/linux/bits/sigstack.h (struct sigstack):
+	Likewise.
+	(stack_t): Likewise.
+	(SS_ONSTACK): Likewise.
+	(SS_DISABLE): Likewise.
+	* sysdeps/unix/sysv/linux/mips/bits/sigstack.h: Likewise.
+	* sysdeps/unix/sysv/linux/ia64/bits/sigstack.h (struct sigstack):
+	Likewise.
+	(stack_t): Likewise.
+	(SS_ONSTACK): Likewise.
+	(SS_DISABLE): Likewise.
+	* sysdeps/unix/sysv/linux/powerpc/bits/sigstack.h
+	(struct sigstack): Likewise.
+	(stack_t): Likewise.
+	(SS_ONSTACK): Likewise.
+	(SS_DISABLE): Likewise.
+	* sysdeps/unix/sysv/linux/sparc/bits/sigstack.h (struct sigstack):
+	Likewise.
+	(stack_t): Likewise.
+	(SS_ONSTACK): Likewise.
+	(SS_DISABLE): Likewise.
+	* sysdeps/arm/sys/ucontext.h: Include
+	<bits/types/struct_sigstack.h>, <bits/types/stack_t.h> and
+	<bits/ss_flags.h>.
+	* sysdeps/generic/sys/ucontext.h: Likewise.
+	* sysdeps/i386/sys/ucontext.h: Likewise.
+	* sysdeps/m68k/sys/ucontext.h: Likewise.
+	* sysdeps/mips/sys/ucontext.h: Likewise.
+	* sysdeps/unix/sysv/linux/aarch64/sys/ucontext.h: Likewise.
+	* sysdeps/unix/sysv/linux/alpha/sys/ucontext.h: Likewise.
+	* sysdeps/unix/sysv/linux/arm/sys/ucontext.h: Likewise.
+	* sysdeps/unix/sysv/linux/hppa/sys/ucontext.h: Likewise.
+	* sysdeps/unix/sysv/linux/ia64/bits/sigcontext.h: Likewise.
+	* sysdeps/unix/sysv/linux/ia64/sys/ucontext.h: Likewise.
+	* sysdeps/unix/sysv/linux/m68k/sys/ucontext.h: Likewise.
+	* sysdeps/unix/sysv/linux/mips/sys/ucontext.h: Likewise.
+	* sysdeps/unix/sysv/linux/nios2/sys/ucontext.h: Likewise.
+	* sysdeps/unix/sysv/linux/powerpc/sys/ucontext.h: Likewise.
+	* sysdeps/unix/sysv/linux/s390/sys/ucontext.h: Likewise.
+	* sysdeps/unix/sysv/linux/sh/sys/ucontext.h: Likewise.
+	* sysdeps/unix/sysv/linux/sparc/sys/ucontext.h: Likewise.
+	* sysdeps/unix/sysv/linux/tile/sys/ucontext.h: Likewise.
+	* sysdeps/unix/sysv/linux/x86/sys/ucontext.h: Likewise.
+
 2017-05-19  H.J. Lu  <hongjiu.lu@intel.com>
 
 	* sysdeps/i386/i686/multiarch/memchr-sse2.S (MEMCHR): Use
diff --git a/bits/sigstack.h b/bits/sigstack.h
index 42143e363a..3127c325e5 100644
--- a/bits/sigstack.h
+++ b/bits/sigstack.h
@@ -23,33 +23,6 @@
 # error "Never include this file directly.  Use <signal.h> instead"
 #endif
 
-
-/* Structure describing a signal stack (obsolete).  */
-struct sigstack
-  {
-    __ptr_t ss_sp;		/* Signal stack pointer.  */
-    int ss_onstack;		/* Nonzero if executing on this stack.  */
-  };
-
-
-/* Alternate, preferred interface.  */
-typedef struct sigaltstack
-  {
-    __ptr_t ss_sp;
-    size_t ss_size;
-    int ss_flags;
-  } stack_t;
-
-
-/* Possible values for `ss_flags.'.  */
-enum
-{
-  SS_ONSTACK = 0x0001,
-#define SS_ONSTACK	SS_ONSTACK
-  SS_DISABLE = 0x0004
-#define SS_DISABLE	SS_DISABLE
-};
-
 /* Minumum stack size for a signal handler.  */
 #define MINSIGSTKSZ	8192
 
diff --git a/bits/ss_flags.h b/bits/ss_flags.h
new file mode 100644
index 0000000000..fa3836c122
--- /dev/null
+++ b/bits/ss_flags.h
@@ -0,0 +1,35 @@
+/* ss_flags values for stack_t.
+   Copyright (C) 1998-2017 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
+   <http://www.gnu.org/licenses/>.  */
+
+#ifndef _BITS_SS_FLAGS_H
+#define _BITS_SS_FLAGS_H 1
+
+#if !defined _SIGNAL_H && !defined _SYS_UCONTEXT_H
+# error "Never include this file directly.  Use <signal.h> instead"
+#endif
+
+/* Possible values for `ss_flags.'.  */
+enum
+{
+  SS_ONSTACK = 0x0001,
+#define SS_ONSTACK	SS_ONSTACK
+  SS_DISABLE = 0x0004
+#define SS_DISABLE	SS_DISABLE
+};
+
+#endif /* bits/ss_flags.h */
diff --git a/bits/types/stack_t.h b/bits/types/stack_t.h
new file mode 100644
index 0000000000..3cf0a4019a
--- /dev/null
+++ b/bits/types/stack_t.h
@@ -0,0 +1,33 @@
+/* Define stack_t.
+   Copyright (C) 1998-2017 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
+   <http://www.gnu.org/licenses/>.  */
+
+#ifndef __stack_t_defined
+#define __stack_t_defined 1
+
+#define __need_size_t
+#include <stddef.h>
+
+/* Structure describing a signal stack.  */
+typedef struct sigaltstack
+  {
+    void *ss_sp;
+    size_t ss_size;
+    int ss_flags;
+  } stack_t;
+
+#endif
diff --git a/include/bits/types/struct_sigstack.h b/include/bits/types/struct_sigstack.h
new file mode 100644
index 0000000000..05f1ee55b7
--- /dev/null
+++ b/include/bits/types/struct_sigstack.h
@@ -0,0 +1 @@
+#include "../../signal/bits/types/struct_sigstack.h"
diff --git a/signal/Makefile b/signal/Makefile
index b65bf6b408..077aaea6ad 100644
--- a/signal/Makefile
+++ b/signal/Makefile
@@ -24,7 +24,8 @@ include ../Makeconfig
 
 headers	:= signal.h sys/signal.h bits/signum.h bits/sigcontext.h \
 	   bits/sigaction.h bits/sigset.h bits/siginfo.h bits/sigstack.h \
-	   bits/sigthread.h
+	   bits/sigthread.h bits/types/struct_sigstack.h bits/types/stack_t.h \
+	   bits/ss_flags.h
 
 routines	:= signal raise killpg \
 		   sigaction sigprocmask kill \
diff --git a/signal/bits/types/struct_sigstack.h b/signal/bits/types/struct_sigstack.h
new file mode 100644
index 0000000000..5e93ce0091
--- /dev/null
+++ b/signal/bits/types/struct_sigstack.h
@@ -0,0 +1,29 @@
+/* Define struct sigstack.
+   Copyright (C) 1998-2017 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
+   <http://www.gnu.org/licenses/>.  */
+
+#ifndef __sigstack_defined
+#define __sigstack_defined 1
+
+/* Structure describing a signal stack (obsolete).  */
+struct sigstack
+  {
+    void *ss_sp;		/* Signal stack pointer.  */
+    int ss_onstack;		/* Nonzero if executing on this stack.  */
+  };
+
+#endif
diff --git a/signal/signal.h b/signal/signal.h
index 6db2d2f100..d01df3290a 100644
--- a/signal/signal.h
+++ b/signal/signal.h
@@ -314,6 +314,9 @@ extern int sigreturn (struct sigcontext *__scp) __THROW;
 extern int siginterrupt (int __sig, int __interrupt) __THROW;
 
 # include <bits/sigstack.h>
+# include <bits/types/struct_sigstack.h>
+# include <bits/types/stack_t.h>
+# include <bits/ss_flags.h>
 # if defined __USE_XOPEN || defined __USE_XOPEN2K8
 /* This will define `ucontext_t' and `mcontext_t'.  */
 #  include <sys/ucontext.h>
diff --git a/sysdeps/arm/sys/ucontext.h b/sysdeps/arm/sys/ucontext.h
index 09fe418b3c..49d60395dd 100644
--- a/sysdeps/arm/sys/ucontext.h
+++ b/sysdeps/arm/sys/ucontext.h
@@ -27,6 +27,9 @@
    by <signal.h>.  */
 #include <bits/sigcontext.h>
 #include <bits/sigstack.h>
+#include <bits/types/struct_sigstack.h>
+#include <bits/types/stack_t.h>
+#include <bits/ss_flags.h>
 
 
 typedef int greg_t;
diff --git a/sysdeps/generic/sys/ucontext.h b/sysdeps/generic/sys/ucontext.h
index 6c475b5a4a..052c5401cb 100644
--- a/sysdeps/generic/sys/ucontext.h
+++ b/sysdeps/generic/sys/ucontext.h
@@ -29,6 +29,9 @@
    by <signal.h>.  */
 #include <bits/sigcontext.h>
 #include <bits/sigstack.h>
+#include <bits/types/struct_sigstack.h>
+#include <bits/types/stack_t.h>
+#include <bits/ss_flags.h>
 
 
 typedef struct sigcontext mcontext_t;
diff --git a/sysdeps/i386/sys/ucontext.h b/sysdeps/i386/sys/ucontext.h
index c632e50eba..241f270a99 100644
--- a/sysdeps/i386/sys/ucontext.h
+++ b/sysdeps/i386/sys/ucontext.h
@@ -27,6 +27,9 @@
    by <signal.h>.  */
 #include <bits/sigcontext.h>
 #include <bits/sigstack.h>
+#include <bits/types/struct_sigstack.h>
+#include <bits/types/stack_t.h>
+#include <bits/ss_flags.h>
 
 
 /* Type for general register.  */
diff --git a/sysdeps/m68k/sys/ucontext.h b/sysdeps/m68k/sys/ucontext.h
index cbec1db5d6..4e5ec3b090 100644
--- a/sysdeps/m68k/sys/ucontext.h
+++ b/sysdeps/m68k/sys/ucontext.h
@@ -27,6 +27,9 @@
    by <signal.h>.  */
 #include <bits/sigcontext.h>
 #include <bits/sigstack.h>
+#include <bits/types/struct_sigstack.h>
+#include <bits/types/stack_t.h>
+#include <bits/ss_flags.h>
 
 
 /* Type for general register.  */
diff --git a/sysdeps/mips/sys/ucontext.h b/sysdeps/mips/sys/ucontext.h
index 137246f961..cb8fbcd3d2 100644
--- a/sysdeps/mips/sys/ucontext.h
+++ b/sysdeps/mips/sys/ucontext.h
@@ -27,6 +27,9 @@
    by <signal.h>.  */
 #include <bits/sigcontext.h>
 #include <bits/sigstack.h>
+#include <bits/types/struct_sigstack.h>
+#include <bits/types/stack_t.h>
+#include <bits/ss_flags.h>
 
 #include <sgidefs.h>
 
diff --git a/sysdeps/unix/sysv/linux/aarch64/bits/sigstack.h b/sysdeps/unix/sysv/linux/aarch64/bits/sigstack.h
index a1f2accfaa..434b24e926 100644
--- a/sysdeps/unix/sysv/linux/aarch64/bits/sigstack.h
+++ b/sysdeps/unix/sysv/linux/aarch64/bits/sigstack.h
@@ -23,33 +23,6 @@
 # error "Never include this file directly.  Use <signal.h> instead"
 #endif
 
-#define __need_size_t
-#include <stddef.h>
-
-/* Structure describing a signal stack (obsolete).  */
-struct sigstack
-  {
-    void *ss_sp;		/* Signal stack pointer.  */
-    int ss_onstack;		/* Nonzero if executing on this stack.  */
-  };
-
-/* Alternate, preferred interface.  */
-typedef struct sigaltstack
-  {
-    void *ss_sp;
-    int ss_flags;
-    size_t ss_size;
-  } stack_t;
-
-/* Possible values for `ss_flags'.  */
-enum
-{
-  SS_ONSTACK = 1,
-#define SS_ONSTACK	SS_ONSTACK
-  SS_DISABLE
-#define SS_DISABLE	SS_DISABLE
-};
-
 /* Minimum stack size for a signal handler.  */
 #define MINSIGSTKSZ	5120
 
diff --git a/sysdeps/unix/sysv/linux/aarch64/sys/ucontext.h b/sysdeps/unix/sysv/linux/aarch64/sys/ucontext.h
index 536404dd71..1a5fa29ce8 100644
--- a/sysdeps/unix/sysv/linux/aarch64/sys/ucontext.h
+++ b/sysdeps/unix/sysv/linux/aarch64/sys/ucontext.h
@@ -28,6 +28,9 @@
    by <signal.h>.  */
 #include <bits/sigcontext.h>
 #include <bits/sigstack.h>
+#include <bits/types/struct_sigstack.h>
+#include <bits/types/stack_t.h>
+#include <bits/ss_flags.h>
 
 #ifdef __USE_MISC
 # include <sys/procfs.h>
diff --git a/sysdeps/unix/sysv/linux/alpha/bits/sigstack.h b/sysdeps/unix/sysv/linux/alpha/bits/sigstack.h
index bba02126b1..9a30c9d9d5 100644
--- a/sysdeps/unix/sysv/linux/alpha/bits/sigstack.h
+++ b/sysdeps/unix/sysv/linux/alpha/bits/sigstack.h
@@ -23,33 +23,6 @@
 # error "Never include this file directly.  Use <signal.h> instead"
 #endif
 
-#define __need_size_t
-#include <stddef.h>
-
-/* Structure describing a signal stack (obsolete).  */
-struct sigstack
-  {
-    __ptr_t ss_sp;		/* Signal stack pointer.  */
-    int ss_onstack;		/* Nonzero if executing on this stack.  */
-  };
-
-/* Alternate, preferred interface.  */
-typedef struct sigaltstack
-  {
-    __ptr_t ss_sp;
-    int ss_flags;
-    size_t ss_size;
-  } stack_t;
-
-/* Possible values for `ss_flags'.  */
-enum
-{
-  SS_ONSTACK = 1,
-#define SS_ONSTACK	SS_ONSTACK
-  SS_DISABLE
-#define SS_DISABLE	SS_DISABLE
-};
-
 /* Minimum stack size for a signal handler.  */
 #define MINSIGSTKSZ	4096
 
diff --git a/sysdeps/unix/sysv/linux/alpha/sys/ucontext.h b/sysdeps/unix/sysv/linux/alpha/sys/ucontext.h
index dc76e49190..912c61c841 100644
--- a/sysdeps/unix/sysv/linux/alpha/sys/ucontext.h
+++ b/sysdeps/unix/sysv/linux/alpha/sys/ucontext.h
@@ -25,6 +25,9 @@
    by <signal.h>.  */
 #include <bits/sigcontext.h>
 #include <bits/sigstack.h>
+#include <bits/types/struct_sigstack.h>
+#include <bits/types/stack_t.h>
+#include <bits/ss_flags.h>
 
 
 /* Type for general register.  */
diff --git a/sysdeps/unix/sysv/linux/arm/sys/ucontext.h b/sysdeps/unix/sysv/linux/arm/sys/ucontext.h
index aedeccdabe..8a5ea71a20 100644
--- a/sysdeps/unix/sysv/linux/arm/sys/ucontext.h
+++ b/sysdeps/unix/sysv/linux/arm/sys/ucontext.h
@@ -27,6 +27,9 @@
    by <signal.h>.  */
 #include <bits/sigcontext.h>
 #include <bits/sigstack.h>
+#include <bits/types/struct_sigstack.h>
+#include <bits/types/stack_t.h>
+#include <bits/ss_flags.h>
 
 
 #ifdef __USE_MISC
diff --git a/sysdeps/unix/sysv/linux/bits/sigstack.h b/sysdeps/unix/sysv/linux/bits/sigstack.h
index a0c3a9f50d..e6b6c7edcf 100644
--- a/sysdeps/unix/sysv/linux/bits/sigstack.h
+++ b/sysdeps/unix/sysv/linux/bits/sigstack.h
@@ -23,33 +23,6 @@
 # error "Never include this file directly.  Use <signal.h> instead"
 #endif
 
-#define __need_size_t
-#include <stddef.h>
-
-/* Structure describing a signal stack (obsolete).  */
-struct sigstack
-  {
-    void *ss_sp;		/* Signal stack pointer.  */
-    int ss_onstack;		/* Nonzero if executing on this stack.  */
-  };
-
-/* Alternate, preferred interface.  */
-typedef struct sigaltstack
-  {
-    void *ss_sp;
-    int ss_flags;
-    size_t ss_size;
-  } stack_t;
-
-/* Possible values for `ss_flags'.  */
-enum
-{
-  SS_ONSTACK = 1,
-#define SS_ONSTACK	SS_ONSTACK
-  SS_DISABLE
-#define SS_DISABLE	SS_DISABLE
-};
-
 /* Minimum stack size for a signal handler.  */
 #define MINSIGSTKSZ	2048
 
diff --git a/sysdeps/unix/sysv/linux/mips/bits/sigstack.h b/sysdeps/unix/sysv/linux/bits/ss_flags.h
index 215f2ff459..497b613a8c 100644
--- a/sysdeps/unix/sysv/linux/mips/bits/sigstack.h
+++ b/sysdeps/unix/sysv/linux/bits/ss_flags.h
@@ -1,4 +1,4 @@
-/* sigstack, sigaltstack definitions.
+/* ss_flags values for stack_t.  Linux version.
    Copyright (C) 1998-2017 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
@@ -13,34 +13,16 @@
    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
+   License along with the GNU C Library; if not, see
    <http://www.gnu.org/licenses/>.  */
 
-#ifndef _BITS_SIGSTACK_H
-#define _BITS_SIGSTACK_H 1
+#ifndef _BITS_SS_FLAGS_H
+#define _BITS_SS_FLAGS_H 1
 
 #if !defined _SIGNAL_H && !defined _SYS_UCONTEXT_H
 # error "Never include this file directly.  Use <signal.h> instead"
 #endif
 
-#define __need_size_t
-#include <stddef.h>
-
-/* Structure describing a signal stack (obsolete).  */
-struct sigstack
-  {
-    void *ss_sp;		/* Signal stack pointer.  */
-    int ss_onstack;		/* Nonzero if executing on this stack.  */
-  };
-
-/* Alternate, preferred interface.  */
-typedef struct sigaltstack
-  {
-    void *ss_sp;
-    size_t ss_size;
-    int ss_flags;
-  } stack_t;
-
 /* Possible values for `ss_flags'.  */
 enum
 {
@@ -50,10 +32,4 @@ enum
 #define SS_DISABLE	SS_DISABLE
 };
 
-/* Minimum stack size for a signal handler.  */
-#define MINSIGSTKSZ	2048
-
-/* System default stack size.  */
-#define SIGSTKSZ	8192
-
-#endif /* bits/sigstack.h */
+#endif /* bits/ss_flags.h */
diff --git a/sysdeps/unix/sysv/linux/bits/types/stack_t.h b/sysdeps/unix/sysv/linux/bits/types/stack_t.h
new file mode 100644
index 0000000000..497e42b0ff
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/bits/types/stack_t.h
@@ -0,0 +1,33 @@
+/* Define stack_t.  Linux version.
+   Copyright (C) 1998-2017 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
+   <http://www.gnu.org/licenses/>.  */
+
+#ifndef __stack_t_defined
+#define __stack_t_defined 1
+
+#define __need_size_t
+#include <stddef.h>
+
+/* Structure describing a signal stack.  */
+typedef struct sigaltstack
+  {
+    void *ss_sp;
+    int ss_flags;
+    size_t ss_size;
+  } stack_t;
+
+#endif
diff --git a/sysdeps/unix/sysv/linux/hppa/sys/ucontext.h b/sysdeps/unix/sysv/linux/hppa/sys/ucontext.h
index 31eb77e01b..50e585d163 100644
--- a/sysdeps/unix/sysv/linux/hppa/sys/ucontext.h
+++ b/sysdeps/unix/sysv/linux/hppa/sys/ucontext.h
@@ -27,6 +27,9 @@
    by <signal.h>.  */
 #include <bits/sigcontext.h>
 #include <bits/sigstack.h>
+#include <bits/types/struct_sigstack.h>
+#include <bits/types/stack_t.h>
+#include <bits/ss_flags.h>
 
 
 #ifdef __USE_MISC
diff --git a/sysdeps/unix/sysv/linux/ia64/bits/sigcontext.h b/sysdeps/unix/sysv/linux/ia64/bits/sigcontext.h
index c9a068957b..c81463d809 100644
--- a/sysdeps/unix/sysv/linux/ia64/bits/sigcontext.h
+++ b/sysdeps/unix/sysv/linux/ia64/bits/sigcontext.h
@@ -26,6 +26,9 @@
 #define __need_size_t
 #include <stddef.h>
 #include <bits/sigstack.h>
+#include <bits/types/struct_sigstack.h>
+#include <bits/types/stack_t.h>
+#include <bits/ss_flags.h>
 
 struct __ia64_fpreg
   {
diff --git a/sysdeps/unix/sysv/linux/ia64/bits/sigstack.h b/sysdeps/unix/sysv/linux/ia64/bits/sigstack.h
index abae4c985e..aabefbb1e3 100644
--- a/sysdeps/unix/sysv/linux/ia64/bits/sigstack.h
+++ b/sysdeps/unix/sysv/linux/ia64/bits/sigstack.h
@@ -23,33 +23,6 @@
 # error "Never include this file directly.  Use <signal.h> instead"
 #endif
 
-#define __need_size_t
-#include <stddef.h>
-
-/* Structure describing a signal stack (obsolete).  */
-struct sigstack
-  {
-    __ptr_t ss_sp;		/* Signal stack pointer.  */
-    int ss_onstack;		/* Nonzero if executing on this stack.  */
-  };
-
-/* Alternate, preferred interface.  */
-typedef struct sigaltstack
-  {
-    __ptr_t ss_sp;
-    int ss_flags;
-    size_t ss_size;
-  } stack_t;
-
-/* Possible values for `ss_flags'.  */
-enum
-{
-  SS_ONSTACK = 1,
-#define SS_ONSTACK	SS_ONSTACK
-  SS_DISABLE
-#define SS_DISABLE	SS_DISABLE
-};
-
 /* Minimum stack size for a signal handler.
 
    Yes, this should be 131072 but the constant got defined incorrectly
diff --git a/sysdeps/unix/sysv/linux/ia64/sys/ucontext.h b/sysdeps/unix/sysv/linux/ia64/sys/ucontext.h
index b2dab0e29e..17474a55c7 100644
--- a/sysdeps/unix/sysv/linux/ia64/sys/ucontext.h
+++ b/sysdeps/unix/sysv/linux/ia64/sys/ucontext.h
@@ -25,6 +25,9 @@
    by <signal.h>.  */
 #include <bits/sigcontext.h>
 #include <bits/sigstack.h>
+#include <bits/types/struct_sigstack.h>
+#include <bits/types/stack_t.h>
+#include <bits/ss_flags.h>
 
 
 /*
diff --git a/sysdeps/unix/sysv/linux/m68k/sys/ucontext.h b/sysdeps/unix/sysv/linux/m68k/sys/ucontext.h
index 3c5dce5b73..18ff02233f 100644
--- a/sysdeps/unix/sysv/linux/m68k/sys/ucontext.h
+++ b/sysdeps/unix/sysv/linux/m68k/sys/ucontext.h
@@ -27,6 +27,9 @@
    by <signal.h>.  */
 #include <bits/sigcontext.h>
 #include <bits/sigstack.h>
+#include <bits/types/struct_sigstack.h>
+#include <bits/types/stack_t.h>
+#include <bits/ss_flags.h>
 
 
 /* Type for general register.  */
diff --git a/sysdeps/unix/sysv/linux/mips/bits/types/stack_t.h b/sysdeps/unix/sysv/linux/mips/bits/types/stack_t.h
new file mode 100644
index 0000000000..ef06072e94
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/mips/bits/types/stack_t.h
@@ -0,0 +1,33 @@
+/* Define stack_t.  MIPS Linux version.
+   Copyright (C) 1998-2017 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
+   <http://www.gnu.org/licenses/>.  */
+
+#ifndef __stack_t_defined
+#define __stack_t_defined 1
+
+#define __need_size_t
+#include <stddef.h>
+
+/* Structure describing a signal stack.  */
+typedef struct sigaltstack
+  {
+    void *ss_sp;
+    size_t ss_size;
+    int ss_flags;
+  } stack_t;
+
+#endif
diff --git a/sysdeps/unix/sysv/linux/mips/sys/ucontext.h b/sysdeps/unix/sysv/linux/mips/sys/ucontext.h
index f766dacd20..f933780dbe 100644
--- a/sysdeps/unix/sysv/linux/mips/sys/ucontext.h
+++ b/sysdeps/unix/sysv/linux/mips/sys/ucontext.h
@@ -26,6 +26,9 @@
    by <signal.h>.  */
 #include <bits/sigcontext.h>
 #include <bits/sigstack.h>
+#include <bits/types/struct_sigstack.h>
+#include <bits/types/stack_t.h>
+#include <bits/ss_flags.h>
 
 #include <sgidefs.h>
 
diff --git a/sysdeps/unix/sysv/linux/nios2/sys/ucontext.h b/sysdeps/unix/sysv/linux/nios2/sys/ucontext.h
index 3b0a615abe..c961e5be40 100644
--- a/sysdeps/unix/sysv/linux/nios2/sys/ucontext.h
+++ b/sysdeps/unix/sysv/linux/nios2/sys/ucontext.h
@@ -28,6 +28,9 @@
    by <signal.h>.  */
 #include <bits/sigcontext.h>
 #include <bits/sigstack.h>
+#include <bits/types/struct_sigstack.h>
+#include <bits/types/stack_t.h>
+#include <bits/ss_flags.h>
 
 
 /* These definitions must be in sync with the kernel.  */
diff --git a/sysdeps/unix/sysv/linux/powerpc/bits/sigstack.h b/sysdeps/unix/sysv/linux/powerpc/bits/sigstack.h
index 4a36ad1a4e..74670cb037 100644
--- a/sysdeps/unix/sysv/linux/powerpc/bits/sigstack.h
+++ b/sysdeps/unix/sysv/linux/powerpc/bits/sigstack.h
@@ -23,33 +23,6 @@
 # error "Never include this file directly.  Use <signal.h> instead"
 #endif
 
-#define __need_size_t
-#include <stddef.h>
-
-/* Structure describing a signal stack (obsolete).  */
-struct sigstack
-  {
-    void *ss_sp;		/* Signal stack pointer.  */
-    int ss_onstack;		/* Nonzero if executing on this stack.  */
-  };
-
-/* Alternate, preferred interface.  */
-typedef struct sigaltstack
-  {
-    void *ss_sp;
-    int ss_flags;
-    size_t ss_size;
-  } stack_t;
-
-/* Possible values for `ss_flags'.  */
-enum
-{
-  SS_ONSTACK = 1,
-#define SS_ONSTACK	SS_ONSTACK
-  SS_DISABLE
-#define SS_DISABLE	SS_DISABLE
-};
-
 /* Minimum stack size for a signal handler.  */
 #define MINSIGSTKSZ	4096
 
diff --git a/sysdeps/unix/sysv/linux/powerpc/sys/ucontext.h b/sysdeps/unix/sysv/linux/powerpc/sys/ucontext.h
index c3f9622e35..d9fad4cf8b 100644
--- a/sysdeps/unix/sysv/linux/powerpc/sys/ucontext.h
+++ b/sysdeps/unix/sysv/linux/powerpc/sys/ucontext.h
@@ -26,6 +26,9 @@
    by <signal.h>.  */
 #include <bits/sigcontext.h>
 #include <bits/sigstack.h>
+#include <bits/types/struct_sigstack.h>
+#include <bits/types/stack_t.h>
+#include <bits/ss_flags.h>
 
 
 #if __WORDSIZE == 32
diff --git a/sysdeps/unix/sysv/linux/s390/sys/ucontext.h b/sysdeps/unix/sysv/linux/s390/sys/ucontext.h
index 9790c0cd7c..955a8fef9c 100644
--- a/sysdeps/unix/sysv/linux/s390/sys/ucontext.h
+++ b/sysdeps/unix/sysv/linux/s390/sys/ucontext.h
@@ -26,6 +26,9 @@
    by in <signal.h>.  */
 #include <bits/sigcontext.h>
 #include <bits/sigstack.h>
+#include <bits/types/struct_sigstack.h>
+#include <bits/types/stack_t.h>
+#include <bits/ss_flags.h>
 
 
 /* Type for a program status word.  */
diff --git a/sysdeps/unix/sysv/linux/sh/sys/ucontext.h b/sysdeps/unix/sysv/linux/sh/sys/ucontext.h
index 5c6a5e4a7a..3ce381d2c6 100644
--- a/sysdeps/unix/sysv/linux/sh/sys/ucontext.h
+++ b/sysdeps/unix/sysv/linux/sh/sys/ucontext.h
@@ -27,6 +27,9 @@
    by <signal.h>.  */
 #include <bits/sigcontext.h>
 #include <bits/sigstack.h>
+#include <bits/types/struct_sigstack.h>
+#include <bits/types/stack_t.h>
+#include <bits/ss_flags.h>
 
 
 typedef int greg_t;
diff --git a/sysdeps/unix/sysv/linux/sparc/bits/sigstack.h b/sysdeps/unix/sysv/linux/sparc/bits/sigstack.h
index 4a36ad1a4e..74670cb037 100644
--- a/sysdeps/unix/sysv/linux/sparc/bits/sigstack.h
+++ b/sysdeps/unix/sysv/linux/sparc/bits/sigstack.h
@@ -23,33 +23,6 @@
 # error "Never include this file directly.  Use <signal.h> instead"
 #endif
 
-#define __need_size_t
-#include <stddef.h>
-
-/* Structure describing a signal stack (obsolete).  */
-struct sigstack
-  {
-    void *ss_sp;		/* Signal stack pointer.  */
-    int ss_onstack;		/* Nonzero if executing on this stack.  */
-  };
-
-/* Alternate, preferred interface.  */
-typedef struct sigaltstack
-  {
-    void *ss_sp;
-    int ss_flags;
-    size_t ss_size;
-  } stack_t;
-
-/* Possible values for `ss_flags'.  */
-enum
-{
-  SS_ONSTACK = 1,
-#define SS_ONSTACK	SS_ONSTACK
-  SS_DISABLE
-#define SS_DISABLE	SS_DISABLE
-};
-
 /* Minimum stack size for a signal handler.  */
 #define MINSIGSTKSZ	4096
 
diff --git a/sysdeps/unix/sysv/linux/sparc/sys/ucontext.h b/sysdeps/unix/sysv/linux/sparc/sys/ucontext.h
index b8f3ca769e..0d6cbe6e6b 100644
--- a/sysdeps/unix/sysv/linux/sparc/sys/ucontext.h
+++ b/sysdeps/unix/sysv/linux/sparc/sys/ucontext.h
@@ -25,6 +25,9 @@
    by <signal.h>.  */
 #include <bits/sigcontext.h>
 #include <bits/sigstack.h>
+#include <bits/types/struct_sigstack.h>
+#include <bits/types/stack_t.h>
+#include <bits/ss_flags.h>
 
 #include <bits/wordsize.h>
 
diff --git a/sysdeps/unix/sysv/linux/tile/sys/ucontext.h b/sysdeps/unix/sysv/linux/tile/sys/ucontext.h
index 95e6dd68f5..8fc2f13834 100644
--- a/sysdeps/unix/sysv/linux/tile/sys/ucontext.h
+++ b/sysdeps/unix/sysv/linux/tile/sys/ucontext.h
@@ -26,6 +26,9 @@
    by <signal.h>.  */
 #include <bits/sigcontext.h>
 #include <bits/sigstack.h>
+#include <bits/types/struct_sigstack.h>
+#include <bits/types/stack_t.h>
+#include <bits/ss_flags.h>
 
 #ifdef __USE_MISC
 /* Get register type and register names. */
diff --git a/sysdeps/unix/sysv/linux/x86/sys/ucontext.h b/sysdeps/unix/sysv/linux/x86/sys/ucontext.h
index 6dad48fb2c..5dd72acf48 100644
--- a/sysdeps/unix/sysv/linux/x86/sys/ucontext.h
+++ b/sysdeps/unix/sysv/linux/x86/sys/ucontext.h
@@ -25,6 +25,9 @@
    by <signal.h>.  */
 #include <bits/sigcontext.h>
 #include <bits/sigstack.h>
+#include <bits/types/struct_sigstack.h>
+#include <bits/types/stack_t.h>
+#include <bits/ss_flags.h>
 
 
 #ifdef __x86_64__