Remove __need macros from stdio.h and wchar.h.

wint_t is a little finicky because it might be defined by stddef.h, which
belongs to the compiler.

In addition to the _types_, a bunch of other declarations shared between
wctype.h and wchar.h are factored out to their own header.

	* libio/bits/types/FILE.h, libio/bits/types/__FILE.h
	* wcsmbs/bits/types/mbstate_t.h, wcsmbs/bits/types/__mbstate_t.h
	* wcsmbs/bits/types/wint_t.h: New single-type definition files.
	* wctype/bits/wctype-wchar.h: New file holding declarations shared
	between wctype.h and wchar.h.

	* libio/Makefile, wcsmbs/Makefile, wctype/Makefile:
	Install them.

	* include/bits/types/FILE.h, include/bits/types/__FILE.h
	* include/bits/types/mbstate_t.h, include/bits/types/__mbstate_t.h
	* include/bits/types/wint_t.h, include/bits/wcsmbs-wchar.h:
	New wrappers.
	* include/stdio.h, include/wchar.h, include/wctype.h:
	No need to handle __need macros.

	* grp/grp.h, gshadow/gshadow.h, hurd/hurd.h, iconv/gconv.h
	* libio/stdio.h, mach/mach.h, misc/mntent.h, pwd/pwd.h
	* shadow/shadow.h, stdio-common/printf.h, wcsmbs/uchar.h
	* wcsmbs/wchar.h, wctype/wctype.h
	* sysdeps/generic/_G_config.h, sysdeps/unix/sysv/linux/_G_config.h
	Use the new files instead of __need macros.

34 files changed, 357 insertions, 382 deletions

diff --git a/ChangeLog b/ChangeLog
index bd530a8d87..69035e8425 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,28 @@
+2017-06-08  Zack Weinberg  <zackw@panix.com>
+
+	* libio/bits/types/FILE.h, libio/bits/types/__FILE.h
+	* wcsmbs/bits/types/mbstate_t.h, wcsmbs/bits/types/__mbstate_t.h
+	* wcsmbs/bits/types/wint_t.h: New single-type definition files.
+	* wctype/bits/wctype-wchar.h: New file holding declarations shared
+	between wctype.h and wchar.h.
+
+	* libio/Makefile, wcsmbs/Makefile, wctype/Makefile:
+	Install them.
+
+	* include/bits/types/FILE.h, include/bits/types/__FILE.h
+	* include/bits/types/mbstate_t.h, include/bits/types/__mbstate_t.h
+	* include/bits/types/wint_t.h, include/bits/wcsmbs-wchar.h:
+	New wrappers.
+	* include/stdio.h, include/wchar.h, include/wctype.h:
+	No need to handle __need macros.
+
+	* grp/grp.h, gshadow/gshadow.h, hurd/hurd.h, iconv/gconv.h
+	* libio/stdio.h, mach/mach.h, misc/mntent.h, pwd/pwd.h
+	* shadow/shadow.h, stdio-common/printf.h, wcsmbs/uchar.h
+	* wcsmbs/wchar.h, wctype/wctype.h
+	* sysdeps/generic/_G_config.h, sysdeps/unix/sysv/linux/_G_config.h
+	Use the new files instead of __need macros.
+
 2017-06-08  H.J. Lu  <hongjiu.lu@intel.com>
 
 	* string/test-memrchr.c (test_main): Add tests for len == 0
diff --git a/grp/grp.h b/grp/grp.h
index d829e4c626..0f833fff89 100644
--- a/grp/grp.h
+++ b/grp/grp.h
@@ -49,8 +49,7 @@ struct group
 
 
 #ifdef __USE_MISC
-# define __need_FILE
-# include <stdio.h>
+# include <bits/types/FILE.h>
 #endif
 
 
diff --git a/gshadow/gshadow.h b/gshadow/gshadow.h
index a93b3bd8b2..70ab83ddbd 100644
--- a/gshadow/gshadow.h
+++ b/gshadow/gshadow.h
@@ -21,11 +21,9 @@
 #define _GSHADOW_H	1
 
 #include <features.h>
-
 #include <paths.h>
+#include <bits/types/FILE.h>
 
-#define	__need_FILE
-#include <stdio.h>
 #define __need_size_t
 #include <stddef.h>
 
diff --git a/hurd/hurd.h b/hurd/hurd.h
index e51d3c58a7..3caa69fbdf 100644
--- a/hurd/hurd.h
+++ b/hurd/hurd.h
@@ -141,8 +141,7 @@ extern struct mutex _hurd_brk_lock;
 
 extern int _hurd_set_brk (vm_address_t newbrk);
 
-#define __need_FILE
-#include <stdio.h>
+#include <bits/types/FILE.h>
 
 /* Calls to get and set basic ports.  */
 
diff --git a/iconv/gconv.h b/iconv/gconv.h
index 71d91a0ef3..db678dba49 100644
--- a/iconv/gconv.h
+++ b/iconv/gconv.h
@@ -23,9 +23,9 @@
 #define _GCONV_H	1
 
 #include <features.h>
-#define __need_mbstate_t
-#define __need_wint_t
-#include <wchar.h>
+#include <bits/types/__mbstate_t.h>
+#include <bits/types/wint_t.h>
+
 #define __need_size_t
 #define __need_wchar_t
 #include <stddef.h>
diff --git a/include/bits/types/FILE.h b/include/bits/types/FILE.h
new file mode 100644
index 0000000000..09b599baa0
--- /dev/null
+++ b/include/bits/types/FILE.h
@@ -0,0 +1 @@
+#include <libio/bits/types/FILE.h>
diff --git a/include/bits/types/__FILE.h b/include/bits/types/__FILE.h
new file mode 100644
index 0000000000..236f60bacd
--- /dev/null
+++ b/include/bits/types/__FILE.h
@@ -0,0 +1 @@
+#include <libio/bits/types/__FILE.h>
diff --git a/include/bits/types/__mbstate_t.h b/include/bits/types/__mbstate_t.h
new file mode 100644
index 0000000000..13e764e8c9
--- /dev/null
+++ b/include/bits/types/__mbstate_t.h
@@ -0,0 +1 @@
+#include <wcsmbs/bits/types/__mbstate_t.h>
diff --git a/include/bits/types/mbstate_t.h b/include/bits/types/mbstate_t.h
new file mode 100644
index 0000000000..99ec08a91a
--- /dev/null
+++ b/include/bits/types/mbstate_t.h
@@ -0,0 +1 @@
+#include <wcsmbs/bits/types/mbstate_t.h>
diff --git a/include/bits/types/wint_t.h b/include/bits/types/wint_t.h
new file mode 100644
index 0000000000..f1e373d294
--- /dev/null
+++ b/include/bits/types/wint_t.h
@@ -0,0 +1 @@
+#include <wcsmbs/bits/types/wint_t.h>
diff --git a/include/bits/wctype-wchar.h b/include/bits/wctype-wchar.h
new file mode 100644
index 0000000000..8273cd743e
--- /dev/null
+++ b/include/bits/wctype-wchar.h
@@ -0,0 +1 @@
+#include <wctype/bits/wctype-wchar.h>
diff --git a/include/stdio.h b/include/stdio.h
index ed6593ba50..f68f633bd6 100644
--- a/include/stdio.h
+++ b/include/stdio.h
@@ -1,8 +1,6 @@
 #ifndef _STDIO_H
-# if defined _ISOMAC || defined __need_FILE || defined __need___FILE
-#  include <libio/stdio.h>
-# else
-#  include <libio/stdio.h>
+# include <libio/stdio.h>
+# ifndef _ISOMAC
 
 /* Now define the internal interfaces.  */
 
@@ -71,11 +69,11 @@ libc_hidden_proto (__isoc99_vfscanf)
 extern FILE *__new_tmpfile (void);
 extern FILE *__old_tmpfile (void);
 
-
-
 #  define __need_size_t
-#  define __need_wint_t
 #  include <stddef.h>
+
+#  include <bits/types/wint_t.h>
+
 /* Generate a unique file name (and possibly open it).  */
 extern int __path_search (char *__tmpl, size_t __tmpl_len,
 			  const char *__dir, const char *__pfx,
@@ -183,5 +181,5 @@ libc_hidden_proto (__obstack_vprintf_chk)
 extern FILE * __fmemopen (void *buf, size_t len, const char *mode);
 libc_hidden_proto (__fmemopen)
 
-# endif
-#endif
+# endif /* not _ISOMAC */
+#endif /* stdio.h */
diff --git a/include/wchar.h b/include/wchar.h
index a773d56b36..cf76709901 100644
--- a/include/wchar.h
+++ b/include/wchar.h
@@ -1,8 +1,6 @@
 #ifndef _WCHAR_H
-#include <wcsmbs/wchar.h>
-
+# include <wcsmbs/wchar.h>
 # ifndef _ISOMAC
-# ifdef _WCHAR_H
 
 extern __typeof (wcscasecmp_l) __wcscasecmp_l;
 extern __typeof (wcsncasecmp_l) __wcsncasecmp_l;
@@ -219,10 +217,4 @@ extern size_t __mbsrtowcs_l (wchar_t *dst, const char **src, size_t len,
 #  define __mbsinit(state) ((state)->__count == 0)
 
 # endif
-# endif
 #endif
-
-/* Undefine all __need_* constants in case we are included to get those
-   constants but the whole file was already read.  */
-#undef __need_mbstate_t
-#undef __need_wint_t
diff --git a/include/wctype.h b/include/wctype.h
index a71b10377b..5fd3f863ae 100644
--- a/include/wctype.h
+++ b/include/wctype.h
@@ -1,30 +1,7 @@
 #ifndef _WCTYPE_H
+#include <wctype/wctype.h>
 
 #ifndef _ISOMAC
-/* We try to get wint_t from <stddef.h>, but not all GCC versions define it
-   there.  So define it ourselves if it remains undefined.  */
-# define __need_wint_t
-# include <stddef.h>
-# ifndef _WINT_T
-/* Integral type unchanged by default argument promotions that can
-   hold any value corresponding to members of the extended character
-   set, as well as at least one value that does not correspond to any
-   member of the extended character set.  */
-#  define _WINT_T
-typedef unsigned int wint_t;
-# endif
-
-/* Need to repeat these prototypes here, as wctype/wctype.h defines all
-   these as macros and thus we couldn't add libc_hidden_proto.  */
-
-extern int iswalpha (wint_t __wc);
-extern int iswalnum (wint_t __wc);
-extern int iswdigit (wint_t __wc);
-extern int iswlower (wint_t __wc);
-extern int iswspace (wint_t __wc);
-extern int iswxdigit (wint_t __wc);
-extern wint_t towlower (wint_t __wc);
-extern wint_t towupper (wint_t __wc);
 
 libc_hidden_proto (iswalpha)
 libc_hidden_proto (iswalnum)
@@ -34,11 +11,7 @@ libc_hidden_proto (iswspace)
 libc_hidden_proto (iswxdigit)
 libc_hidden_proto (towlower)
 libc_hidden_proto (towupper)
-#endif
-
-#include <wctype/wctype.h>
 
-#ifndef _ISOMAC
 /* Internal interfaces.  */
 extern int __iswspace (wint_t __wc);
 extern int __iswctype (wint_t __wc, wctype_t __desc);
diff --git a/libio/Makefile b/libio/Makefile
index be252f740f..a002a3365c 100644
--- a/libio/Makefile
+++ b/libio/Makefile
@@ -23,7 +23,8 @@ subdir	:= libio
 include ../Makeconfig
 
 headers	:= stdio.h libio.h _G_config.h bits/stdio.h \
-	   bits/sys_errlist.h bits/stdio2.h bits/stdio-ldbl.h bits/libio-ldbl.h
+	   bits/sys_errlist.h bits/stdio2.h bits/stdio-ldbl.h bits/libio-ldbl.h \
+	   bits/types/FILE.h bits/types/__FILE.h
 
 routines	:=							      \
 	filedoalloc iofclose iofdopen iofflush iofgetpos iofgets iofopen      \
diff --git a/libio/bits/types/FILE.h b/libio/bits/types/FILE.h
new file mode 100644
index 0000000000..f268263209
--- /dev/null
+++ b/libio/bits/types/FILE.h
@@ -0,0 +1,9 @@
+#ifndef __FILE_defined
+#define __FILE_defined 1
+
+struct _IO_FILE;
+
+/* The opaque type of streams.  This is the definition used elsewhere.  */
+typedef struct _IO_FILE FILE;
+
+#endif
diff --git a/libio/bits/types/__FILE.h b/libio/bits/types/__FILE.h
new file mode 100644
index 0000000000..06dd79bc83
--- /dev/null
+++ b/libio/bits/types/__FILE.h
@@ -0,0 +1,7 @@
+#ifndef ____FILE_defined
+#define ____FILE_defined 1
+
+struct _IO_FILE;
+typedef struct _IO_FILE __FILE;
+
+#endif
diff --git a/libio/stdio.h b/libio/stdio.h
index 422f39daf5..47490c8299 100644
--- a/libio/stdio.h
+++ b/libio/stdio.h
@@ -21,48 +21,21 @@
  */
 
 #ifndef _STDIO_H
+#define _STDIO_H	1
 
-#if !defined __need_FILE && !defined __need___FILE
-# define _STDIO_H	1
-# define __GLIBC_INTERNAL_STARTING_HEADER_IMPLEMENTATION
-# include <bits/libc-header-start.h>
+#define __GLIBC_INTERNAL_STARTING_HEADER_IMPLEMENTATION
+#include <bits/libc-header-start.h>
 
 __BEGIN_DECLS
 
-# define __need_size_t
-# define __need_NULL
-# include <stddef.h>
+#define __need_size_t
+#define __need_NULL
+#include <stddef.h>
 
-# include <bits/types.h>
-# define __need_FILE
-# define __need___FILE
-#endif /* Don't need FILE.  */
+#include <bits/types.h>
+#include <bits/types/__FILE.h>
+#include <bits/types/FILE.h>
 
-
-#if !defined __FILE_defined && defined __need_FILE
-
-/* Define outside of namespace so the C++ is happy.  */
-struct _IO_FILE;
-
-/* The opaque type of streams.  This is the definition used elsewhere.  */
-typedef struct _IO_FILE FILE;
-
-# define __FILE_defined	1
-#endif /* FILE not defined.  */
-#undef	__need_FILE
-
-
-#if !defined ____FILE_defined && defined __need___FILE
-
-/* The opaque type of streams.  This is the definition used elsewhere.  */
-typedef struct _IO_FILE __FILE;
-
-# define ____FILE_defined	1
-#endif /* __FILE not defined.  */
-#undef	__need___FILE
-
-
-#ifdef	_STDIO_H
 #define _STDIO_USES_IOSTREAM
 
 #include <libio.h>
@@ -895,5 +868,3 @@ extern void funlockfile (FILE *__stream) __THROW;
 __END_DECLS
 
 #endif /* <stdio.h> included.  */
-
-#endif /* !_STDIO_H */
diff --git a/mach/mach.h b/mach/mach.h
index 3ceb7b6c8c..42605af865 100644
--- a/mach/mach.h
+++ b/mach/mach.h
@@ -20,10 +20,8 @@
 
 #define	_MACH_H	1
 
-/* We must include this before using __need_FILE with <stdio.h> below.  */
 #include <features.h>
 
-
 /* Get the basic types used by Mach.  */
 #include <mach/mach_types.h>
 
@@ -79,9 +77,7 @@ extern void
 __mach_msg_destroy (mach_msg_header_t *msg),
 mach_msg_destroy (mach_msg_header_t *msg);
 
-
-#define __need_FILE
-#include <stdio.h>
+#include <bits/types/FILE.h>
 
 /* Open a stream on a Mach device.  */
 extern FILE *mach_open_devstream (mach_port_t device_port, const char *mode);
diff --git a/misc/mntent.h b/misc/mntent.h
index 039a454512..e54e165637 100644
--- a/misc/mntent.h
+++ b/misc/mntent.h
@@ -20,10 +20,8 @@
 #define	_MNTENT_H	1
 
 #include <features.h>
-#define __need_FILE
-#include <stdio.h>
 #include <paths.h>
-
+#include <bits/types/FILE.h>
 
 /* File listing canonical interesting mount points.  */
 #define	MNTTAB		_PATH_MNTTAB	/* Deprecated alias.  */
diff --git a/pwd/pwd.h b/pwd/pwd.h
index fabd95044c..100f33eb4e 100644
--- a/pwd/pwd.h
+++ b/pwd/pwd.h
@@ -59,8 +59,7 @@ struct passwd
 
 
 #ifdef __USE_MISC
-# define __need_FILE
-# include <stdio.h>
+# include <bits/types/FILE.h>
 #endif
 
 
diff --git a/shadow/shadow.h b/shadow/shadow.h
index 855fe632a1..f55c946f59 100644
--- a/shadow/shadow.h
+++ b/shadow/shadow.h
@@ -24,11 +24,11 @@
 
 #include <paths.h>
 
-#define	__need_FILE
-#include <stdio.h>
 #define __need_size_t
 #include <stddef.h>
 
+#include <bits/types/FILE.h>
+
 /* Paths to the user database files.  */
 #define	SHADOW _PATH_SHADOW
 
diff --git a/stdio-common/printf.h b/stdio-common/printf.h
index 6b207d2db7..940256445e 100644
--- a/stdio-common/printf.h
+++ b/stdio-common/printf.h
@@ -22,11 +22,12 @@
 
 __BEGIN_DECLS
 
-#define	__need_FILE
-#include <stdio.h>
+#include <bits/types/FILE.h>
+
 #define	__need_size_t
 #define __need_wchar_t
 #include <stddef.h>
+
 #include <stdarg.h>
 
 
diff --git a/sysdeps/generic/_G_config.h b/sysdeps/generic/_G_config.h
index f44a3d4eee..c49eed395b 100644
--- a/sysdeps/generic/_G_config.h
+++ b/sysdeps/generic/_G_config.h
@@ -13,11 +13,12 @@
 #endif
 #define __need_NULL
 #include <stddef.h>
-#define __need_mbstate_t
+
+#include <bits/types/__mbstate_t.h>
 #if defined _LIBC || defined _GLIBCPP_USE_WCHAR_T
-# define __need_wint_t
+# include <bits/types/wint_t.h>
 #endif
-#include <wchar.h>
+
 typedef struct
 {
   __off_t __pos;
diff --git a/sysdeps/unix/sysv/linux/_G_config.h b/sysdeps/unix/sysv/linux/_G_config.h
index abec245606..3bc6cfd595 100644
--- a/sysdeps/unix/sysv/linux/_G_config.h
+++ b/sysdeps/unix/sysv/linux/_G_config.h
@@ -13,11 +13,12 @@
 #endif
 #define __need_NULL
 #include <stddef.h>
-#define __need_mbstate_t
+
+#include <bits/types/__mbstate_t.h>
 #if defined _LIBC || defined _GLIBCPP_USE_WCHAR_T
-# define __need_wint_t
+# include <bits/types/wint_t.h>
 #endif
-#include <wchar.h>
+
 typedef struct
 {
   __off_t __pos;
diff --git a/wcsmbs/Makefile b/wcsmbs/Makefile
index d6b214b2ab..08b1de11a8 100644
--- a/wcsmbs/Makefile
+++ b/wcsmbs/Makefile
@@ -22,7 +22,8 @@ subdir	:= wcsmbs
 
 include ../Makeconfig
 
-headers	:= wchar.h bits/wchar.h bits/wchar2.h bits/wchar-ldbl.h uchar.h
+headers	:= wchar.h bits/wchar.h bits/wchar2.h bits/wchar-ldbl.h uchar.h \
+	   bits/types/__mbstate_t.h bits/types/mbstate_t.h bits/types/wint_t.h
 
 routines := wcscat wcschr wcscmp wcscpy wcscspn wcsdup wcslen wcsncat \
 	    wcsncmp wcsncpy wcspbrk wcsrchr wcsspn wcstok wcsstr wmemchr \
diff --git a/wcsmbs/bits/types/__mbstate_t.h b/wcsmbs/bits/types/__mbstate_t.h
new file mode 100644
index 0000000000..1d8a4e28d1
--- /dev/null
+++ b/wcsmbs/bits/types/__mbstate_t.h
@@ -0,0 +1,23 @@
+#ifndef ____mbstate_t_defined
+#define ____mbstate_t_defined 1
+
+/* Integral type unchanged by default argument promotions that can
+   hold any value corresponding to members of the extended character
+   set, as well as at least one value that does not correspond to any
+   member of the extended character set.  */
+#ifndef __WINT_TYPE__
+# define __WINT_TYPE__ unsigned int
+#endif
+
+/* Conversion state information.  */
+typedef struct
+{
+  int __count;
+  union
+  {
+    __WINT_TYPE__ __wch;
+    char __wchb[4];
+  } __value;		/* Value so far.  */
+} __mbstate_t;
+
+#endif
diff --git a/wcsmbs/bits/types/mbstate_t.h b/wcsmbs/bits/types/mbstate_t.h
new file mode 100644
index 0000000000..8d1baa5c3b
--- /dev/null
+++ b/wcsmbs/bits/types/mbstate_t.h
@@ -0,0 +1,8 @@
+#ifndef __mbstate_t_defined
+#define __mbstate_t_defined 1
+
+#include <bits/types/__mbstate_t.h>
+
+typedef __mbstate_t mbstate_t;
+
+#endif
diff --git a/wcsmbs/bits/types/wint_t.h b/wcsmbs/bits/types/wint_t.h
new file mode 100644
index 0000000000..fbd63dbc84
--- /dev/null
+++ b/wcsmbs/bits/types/wint_t.h
@@ -0,0 +1,23 @@
+#ifndef __wint_t_defined
+#define __wint_t_defined 1
+
+/* Some versions of stddef.h provide wint_t, even though neither the
+   C nor C++ standards, nor POSIX, specifies this.  We assume that
+   stddef.h will define the macro _WINT_T if and only if it provides
+   wint_t, and conversely, that it will avoid providing wint_t if
+   _WINT_T is already defined.  */
+#ifndef _WINT_T
+#define _WINT_T 1
+
+/* Integral type unchanged by default argument promotions that can
+   hold any value corresponding to members of the extended character
+   set, as well as at least one value that does not correspond to any
+   member of the extended character set.  */
+#ifndef __WINT_TYPE__
+# define __WINT_TYPE__ unsigned int
+#endif
+
+typedef __WINT_TYPE__ wint_t;
+
+#endif /* _WINT_T */
+#endif /* bits/types/wint_t.h */
diff --git a/wcsmbs/uchar.h b/wcsmbs/uchar.h
index a6569825fd..f937519cf4 100644
--- a/wcsmbs/uchar.h
+++ b/wcsmbs/uchar.h
@@ -27,15 +27,8 @@
 
 #define __need_size_t
 #include <stddef.h>
-#define __need_mbstate_t
-#include <wchar.h>
-
-#ifndef __mbstate_t_defined
-/* Public type.  */
-typedef __mbstate_t mbstate_t;
-# define __mbstate_t_defined 1
-#endif
 
+#include <bits/types/mbstate_t.h>
 
 #if defined __GNUC__ && !defined __USE_ISOCXX11
 /* Define the 16-bit and 32-bit character types.  Use the information
diff --git a/wcsmbs/wchar.h b/wcsmbs/wchar.h
index 79be9fc41d..d389428daa 100644
--- a/wcsmbs/wchar.h
+++ b/wcsmbs/wchar.h
@@ -21,82 +21,32 @@
  */
 
 #ifndef _WCHAR_H
+#define _WCHAR_H 1
 
-#if !defined __need_mbstate_t && !defined __need_wint_t
-# define _WCHAR_H 1
-# define __GLIBC_INTERNAL_STARTING_HEADER_IMPLEMENTATION
-# include <bits/libc-header-start.h>
-#endif
+#define __GLIBC_INTERNAL_STARTING_HEADER_IMPLEMENTATION
+#include <bits/libc-header-start.h>
 
-#ifdef _WCHAR_H
-/* Get FILE definition.  */
-# define __need___FILE
-# if defined __USE_UNIX98 || defined __USE_XOPEN2K
-#  define __need_FILE
-# endif
-# include <stdio.h>
-/* Get va_list definition.  */
-# define __need___va_list
-# include <stdarg.h>
+#define __need_size_t
+#define __need_wchar_t
+#define __need_NULL
+#include <stddef.h>
 
-# include <bits/wchar.h>
+#define __need___va_list
+#include <stdarg.h>
 
-/* Get size_t, wchar_t, wint_t and NULL from <stddef.h>.  */
-# define __need_size_t
-# define __need_wchar_t
-# define __need_NULL
-#endif
-#if defined _WCHAR_H || defined __need_wint_t || !defined __WINT_TYPE__
-# undef __need_wint_t
-# define __need_wint_t
-# include <stddef.h>
-
-/* We try to get wint_t from <stddef.h>, but not all GCC versions define it
-   there.  So define it ourselves if it remains undefined.  */
-# ifndef _WINT_T
-/* Integral type unchanged by default argument promotions that can
-   hold any value corresponding to members of the extended character
-   set, as well as at least one value that does not correspond to any
-   member of the extended character set.  */
-#  define _WINT_T
-typedef unsigned int wint_t;
-# endif
+#include <bits/wchar.h>
+#include <bits/types/wint_t.h>
+#include <bits/types/mbstate_t.h>
+#include <bits/types/__FILE.h>
 
-/* Tell the caller that we provide correct C++ prototypes.  */
-# if defined __cplusplus && __GNUC_PREREQ (4, 4)
-#  define __CORRECT_ISO_CPP_WCHAR_H_PROTO
-# endif
+#if defined __USE_UNIX98 || defined __USE_XOPEN2K
+# include <bits/types/FILE.h>
 #endif
 
-#if (defined _WCHAR_H || defined __need_mbstate_t) && !defined ____mbstate_t_defined
-# define ____mbstate_t_defined	1
-/* Conversion state information.  */
-typedef struct
-{
-  int __count;
-  union
-  {
-# ifdef __WINT_TYPE__
-    __WINT_TYPE__ __wch;
-# else
-    wint_t __wch;
-# endif
-    char __wchb[4];
-  } __value;		/* Value so far.  */
-} __mbstate_t;
+/* Tell the caller that we provide correct C++ prototypes.  */
+#if defined __cplusplus && __GNUC_PREREQ (4, 4)
+# define __CORRECT_ISO_CPP_WCHAR_H_PROTO
 #endif
-#undef __need_mbstate_t
-
-
-/* The rest of the file is only used if used if __need_mbstate_t is not
-   defined.  */
-#ifdef _WCHAR_H
-
-# ifndef __mbstate_t_defined
-/* Public type.  */
-typedef __mbstate_t mbstate_t;
-#  define __mbstate_t_defined 1
-# endif
 
 #ifndef WCHAR_MIN
 /* These constants might also be defined in <inttypes.h>.  */
@@ -108,13 +58,18 @@ typedef __mbstate_t mbstate_t;
 # define WEOF (0xffffffffu)
 #endif
 
-/* For XPG4 compliance we have to define the stuff from <wctype.h> here
-   as well.  */
-#if defined __USE_XOPEN && !defined __USE_UNIX98
-# include <wctype.h>
+/* All versions of XPG prior to the publication of ISO C99 required
+   the bulk of <wctype.h>'s declarations to appear in this header
+   (because <wctype.h> did not exist prior to C99).  In POSIX.1-2001
+   those declarations were marked as XSI extensions; in -2008 they
+   were additionally marked as obsolescent.  _GNU_SOURCE mode
+   anticipates the removal of these declarations in the next revision
+   of POSIX.  */
+#if (defined __USE_XOPEN && !defined __USE_GNU \
+     && !(defined __USE_XOPEN2K && !defined __USE_XOPEN2KXSI))
+# include <bits/wctype-wchar.h>
 #endif
 
-
 __BEGIN_DECLS
 
 /* This incomplete type is defined in <time.h> but needed here because
@@ -823,17 +778,6 @@ extern size_t wcsftime_l (wchar_t *__restrict __s, size_t __maxsize,
 			  __locale_t __loc) __THROW;
 # endif
 
-/* The X/Open standard demands that most of the functions defined in
-   the <wctype.h> header must also appear here.  This is probably
-   because some X/Open members wrote their implementation before the
-   ISO C standard was published and introduced the better solution.
-   We have to provide these definitions for compliance reasons but we
-   do this nonsense only if really necessary.  */
-#if defined __USE_UNIX98 && !defined __USE_GNU
-# define __need_iswxxx
-# include <wctype.h>
-#endif
-
 /* Define some macros helping to catch buffer overflows.  */
 #if __USE_FORTIFY_LEVEL > 0 && defined __fortify_function
 # include <bits/wchar2.h>
@@ -845,11 +789,4 @@ extern size_t wcsftime_l (wchar_t *__restrict __s, size_t __maxsize,
 
 __END_DECLS
 
-#endif	/* _WCHAR_H defined */
-
 #endif /* wchar.h  */
-
-/* Undefine all __need_* constants in case we are included to get those
-   constants but the whole file was already read.  */
-#undef __need_mbstate_t
-#undef __need_wint_t
diff --git a/wctype/Makefile b/wctype/Makefile
index 18756c38e6..2cb2a6dc86 100644
--- a/wctype/Makefile
+++ b/wctype/Makefile
@@ -22,7 +22,7 @@ subdir	:= wctype
 
 include ../Makeconfig
 
-headers		:= wctype.h
+headers		:= wctype.h bits/wctype-wchar.h
 routines	:= wcfuncs wctype iswctype wctrans towctrans \
 		   wcfuncs_l wctype_l iswctype_l wctrans_l towctrans_l
 
diff --git a/wctype/bits/wctype-wchar.h b/wctype/bits/wctype-wchar.h
new file mode 100644
index 0000000000..df5fd0396f
--- /dev/null
+++ b/wctype/bits/wctype-wchar.h
@@ -0,0 +1,173 @@
+/* Copyright (C) 1996-2016 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/>.  */
+
+/*
+ *	ISO C99 Standard: 7.25
+ *	Wide character classification and mapping utilities  <wctype.h>
+ */
+
+#ifndef _BITS_WCTYPE_WCHAR_H
+#define _BITS_WCTYPE_WCHAR_H 1
+
+#if !defined _WCTYPE_H && !defined _WCHAR_H
+#error "Never include <bits/wctype-wchar.h> directly; include <wctype.h> or <wchar.h> instead."
+#endif
+
+#include <bits/types.h>
+#include <bits/types/wint_t.h>
+
+/* The definitions in this header are specified to appear in <wctype.h>
+   in ISO C99, but in <wchar.h> in Unix98.  _GNU_SOURCE follows C99.  */
+
+/* Scalar type that can hold values which represent locale-specific
+   character classifications.  */
+typedef unsigned long int wctype_t;
+
+# ifndef _ISwbit
+/* The characteristics are stored always in network byte order (big
+   endian).  We define the bit value interpretations here dependent on the
+   machine's byte order.  */
+
+#  include <endian.h>
+#  if __BYTE_ORDER == __BIG_ENDIAN
+#   define _ISwbit(bit)	(1 << (bit))
+#  else /* __BYTE_ORDER == __LITTLE_ENDIAN */
+#   define _ISwbit(bit)	\
+	((bit) < 8 ? (int) ((1UL << (bit)) << 24)			      \
+	 : ((bit) < 16 ? (int) ((1UL << (bit)) << 8)			      \
+	    : ((bit) < 24 ? (int) ((1UL << (bit)) >> 8)			      \
+	       : (int) ((1UL << (bit)) >> 24))))
+#  endif
+
+enum
+{
+  __ISwupper = 0,			/* UPPERCASE.  */
+  __ISwlower = 1,			/* lowercase.  */
+  __ISwalpha = 2,			/* Alphabetic.  */
+  __ISwdigit = 3,			/* Numeric.  */
+  __ISwxdigit = 4,			/* Hexadecimal numeric.  */
+  __ISwspace = 5,			/* Whitespace.  */
+  __ISwprint = 6,			/* Printing.  */
+  __ISwgraph = 7,			/* Graphical.  */
+  __ISwblank = 8,			/* Blank (usually SPC and TAB).  */
+  __ISwcntrl = 9,			/* Control character.  */
+  __ISwpunct = 10,			/* Punctuation.  */
+  __ISwalnum = 11,			/* Alphanumeric.  */
+
+  _ISwupper = _ISwbit (__ISwupper),	/* UPPERCASE.  */
+  _ISwlower = _ISwbit (__ISwlower),	/* lowercase.  */
+  _ISwalpha = _ISwbit (__ISwalpha),	/* Alphabetic.  */
+  _ISwdigit = _ISwbit (__ISwdigit),	/* Numeric.  */
+  _ISwxdigit = _ISwbit (__ISwxdigit),	/* Hexadecimal numeric.  */
+  _ISwspace = _ISwbit (__ISwspace),	/* Whitespace.  */
+  _ISwprint = _ISwbit (__ISwprint),	/* Printing.  */
+  _ISwgraph = _ISwbit (__ISwgraph),	/* Graphical.  */
+  _ISwblank = _ISwbit (__ISwblank),	/* Blank (usually SPC and TAB).  */
+  _ISwcntrl = _ISwbit (__ISwcntrl),	/* Control character.  */
+  _ISwpunct = _ISwbit (__ISwpunct),	/* Punctuation.  */
+  _ISwalnum = _ISwbit (__ISwalnum)	/* Alphanumeric.  */
+};
+# endif /* Not _ISwbit  */
+
+
+__BEGIN_DECLS
+
+/*
+ * Wide-character classification functions: 7.15.2.1.
+ */
+
+/* Test for any wide character for which `iswalpha' or `iswdigit' is
+   true.  */
+extern int iswalnum (wint_t __wc) __THROW;
+
+/* Test for any wide character for which `iswupper' or 'iswlower' is
+   true, or any wide character that is one of a locale-specific set of
+   wide-characters for which none of `iswcntrl', `iswdigit',
+   `iswpunct', or `iswspace' is true.  */
+extern int iswalpha (wint_t __wc) __THROW;
+
+/* Test for any control wide character.  */
+extern int iswcntrl (wint_t __wc) __THROW;
+
+/* Test for any wide character that corresponds to a decimal-digit
+   character.  */
+extern int iswdigit (wint_t __wc) __THROW;
+
+/* Test for any wide character for which `iswprint' is true and
+   `iswspace' is false.  */
+extern int iswgraph (wint_t __wc) __THROW;
+
+/* Test for any wide character that corresponds to a lowercase letter
+   or is one of a locale-specific set of wide characters for which
+   none of `iswcntrl', `iswdigit', `iswpunct', or `iswspace' is true.  */
+extern int iswlower (wint_t __wc) __THROW;
+
+/* Test for any printing wide character.  */
+extern int iswprint (wint_t __wc) __THROW;
+
+/* Test for any printing wide character that is one of a
+   locale-specific et of wide characters for which neither `iswspace'
+   nor `iswalnum' is true.  */
+extern int iswpunct (wint_t __wc) __THROW;
+
+/* Test for any wide character that corresponds to a locale-specific
+   set of wide characters for which none of `iswalnum', `iswgraph', or
+   `iswpunct' is true.  */
+extern int iswspace (wint_t __wc) __THROW;
+
+/* Test for any wide character that corresponds to an uppercase letter
+   or is one of a locale-specific set of wide character for which none
+   of `iswcntrl', `iswdigit', `iswpunct', or `iswspace' is true.  */
+extern int iswupper (wint_t __wc) __THROW;
+
+/* Test for any wide character that corresponds to a hexadecimal-digit
+   character equivalent to that performed be the functions described
+   in the previous subclause.  */
+extern int iswxdigit (wint_t __wc) __THROW;
+
+/* Test for any wide character that corresponds to a standard blank
+   wide character or a locale-specific set of wide characters for
+   which `iswalnum' is false.  */
+# ifdef __USE_ISOC99
+extern int iswblank (wint_t __wc) __THROW;
+# endif
+
+/*
+ * Extensible wide-character classification functions: 7.15.2.2.
+ */
+
+/* Construct value that describes a class of wide characters identified
+   by the string argument PROPERTY.  */
+extern wctype_t wctype (const char *__property) __THROW;
+
+/* Determine whether the wide-character WC has the property described by
+   DESC.  */
+extern int iswctype (wint_t __wc, wctype_t __desc) __THROW;
+
+/*
+ * Wide-character case-mapping functions: 7.15.3.1.
+ */
+
+/* Converts an uppercase letter to the corresponding lowercase letter.  */
+extern wint_t towlower (wint_t __wc) __THROW;
+
+/* Converts an lowercase letter to the corresponding uppercase letter.  */
+extern wint_t towupper (wint_t __wc) __THROW;
+
+__END_DECLS
+
+#endif /* bits/wctype-wchar.h.  */
diff --git a/wctype/wctype.h b/wctype/wctype.h
index 73165bbda2..962aef1de6 100644
--- a/wctype/wctype.h
+++ b/wctype/wctype.h
@@ -21,186 +21,32 @@
  */
 
 #ifndef _WCTYPE_H
+#define _WCTYPE_H 1
 
 #include <features.h>
 #include <bits/types.h>
-
-#ifndef __need_iswxxx
-# define _WCTYPE_H	1
-
-/* Get wint_t from <wchar.h>.  */
-# define __need_wint_t
-# include <wchar.h>
+#include <bits/types/wint_t.h>
 
 /* Constant expression of type `wint_t' whose value does not correspond
    to any member of the extended character set.  */
-# ifndef WEOF
-#  define WEOF (0xffffffffu)
-# endif
+#ifndef WEOF
+# define WEOF (0xffffffffu)
 #endif
-#undef __need_iswxxx
-
-
-/* The following part is also used in the <wcsmbs.h> header when compiled
-   in the Unix98 compatibility mode.  */
-#ifndef __iswxxx_defined
-# define __iswxxx_defined	1
-
-/* Scalar type that can hold values which represent locale-specific
-   character classifications.  */
-typedef unsigned long int wctype_t;
-
-# ifndef _ISwbit
-/* The characteristics are stored always in network byte order (big
-   endian).  We define the bit value interpretations here dependent on the
-   machine's byte order.  */
-
-#  include <endian.h>
-#  if __BYTE_ORDER == __BIG_ENDIAN
-#   define _ISwbit(bit)	(1 << (bit))
-#  else /* __BYTE_ORDER == __LITTLE_ENDIAN */
-#   define _ISwbit(bit)	\
-	((bit) < 8 ? (int) ((1UL << (bit)) << 24)			      \
-	 : ((bit) < 16 ? (int) ((1UL << (bit)) << 8)			      \
-	    : ((bit) < 24 ? (int) ((1UL << (bit)) >> 8)			      \
-	       : (int) ((1UL << (bit)) >> 24))))
-#  endif
-
-enum
-{
-  __ISwupper = 0,			/* UPPERCASE.  */
-  __ISwlower = 1,			/* lowercase.  */
-  __ISwalpha = 2,			/* Alphabetic.  */
-  __ISwdigit = 3,			/* Numeric.  */
-  __ISwxdigit = 4,			/* Hexadecimal numeric.  */
-  __ISwspace = 5,			/* Whitespace.  */
-  __ISwprint = 6,			/* Printing.  */
-  __ISwgraph = 7,			/* Graphical.  */
-  __ISwblank = 8,			/* Blank (usually SPC and TAB).  */
-  __ISwcntrl = 9,			/* Control character.  */
-  __ISwpunct = 10,			/* Punctuation.  */
-  __ISwalnum = 11,			/* Alphanumeric.  */
-
-  _ISwupper = _ISwbit (__ISwupper),	/* UPPERCASE.  */
-  _ISwlower = _ISwbit (__ISwlower),	/* lowercase.  */
-  _ISwalpha = _ISwbit (__ISwalpha),	/* Alphabetic.  */
-  _ISwdigit = _ISwbit (__ISwdigit),	/* Numeric.  */
-  _ISwxdigit = _ISwbit (__ISwxdigit),	/* Hexadecimal numeric.  */
-  _ISwspace = _ISwbit (__ISwspace),	/* Whitespace.  */
-  _ISwprint = _ISwbit (__ISwprint),	/* Printing.  */
-  _ISwgraph = _ISwbit (__ISwgraph),	/* Graphical.  */
-  _ISwblank = _ISwbit (__ISwblank),	/* Blank (usually SPC and TAB).  */
-  _ISwcntrl = _ISwbit (__ISwcntrl),	/* Control character.  */
-  _ISwpunct = _ISwbit (__ISwpunct),	/* Punctuation.  */
-  _ISwalnum = _ISwbit (__ISwalnum)	/* Alphanumeric.  */
-};
-# endif /* Not _ISwbit  */
 
-
-__BEGIN_DECLS
+/* Some definitions from this header also appear in <wchar.h> in
+   Unix98 mode.  */
+#include <bits/wctype-wchar.h>
 
 /*
- * Wide-character classification functions: 7.15.2.1.
- */
-
-/* Test for any wide character for which `iswalpha' or `iswdigit' is
-   true.  */
-extern int iswalnum (wint_t __wc) __THROW;
-
-/* Test for any wide character for which `iswupper' or 'iswlower' is
-   true, or any wide character that is one of a locale-specific set of
-   wide-characters for which none of `iswcntrl', `iswdigit',
-   `iswpunct', or `iswspace' is true.  */
-extern int iswalpha (wint_t __wc) __THROW;
-
-/* Test for any control wide character.  */
-extern int iswcntrl (wint_t __wc) __THROW;
-
-/* Test for any wide character that corresponds to a decimal-digit
-   character.  */
-extern int iswdigit (wint_t __wc) __THROW;
-
-/* Test for any wide character for which `iswprint' is true and
-   `iswspace' is false.  */
-extern int iswgraph (wint_t __wc) __THROW;
-
-/* Test for any wide character that corresponds to a lowercase letter
-   or is one of a locale-specific set of wide characters for which
-   none of `iswcntrl', `iswdigit', `iswpunct', or `iswspace' is true.  */
-extern int iswlower (wint_t __wc) __THROW;
-
-/* Test for any printing wide character.  */
-extern int iswprint (wint_t __wc) __THROW;
-
-/* Test for any printing wide character that is one of a
-   locale-specific et of wide characters for which neither `iswspace'
-   nor `iswalnum' is true.  */
-extern int iswpunct (wint_t __wc) __THROW;
-
-/* Test for any wide character that corresponds to a locale-specific
-   set of wide characters for which none of `iswalnum', `iswgraph', or
-   `iswpunct' is true.  */
-extern int iswspace (wint_t __wc) __THROW;
-
-/* Test for any wide character that corresponds to an uppercase letter
-   or is one of a locale-specific set of wide character for which none
-   of `iswcntrl', `iswdigit', `iswpunct', or `iswspace' is true.  */
-extern int iswupper (wint_t __wc) __THROW;
-
-/* Test for any wide character that corresponds to a hexadecimal-digit
-   character equivalent to that performed be the functions described
-   in the previous subclause.  */
-extern int iswxdigit (wint_t __wc) __THROW;
-
-/* Test for any wide character that corresponds to a standard blank
-   wide character or a locale-specific set of wide characters for
-   which `iswalnum' is false.  */
-# ifdef __USE_ISOC99
-extern int iswblank (wint_t __wc) __THROW;
-# endif
-
-/*
- * Extensible wide-character classification functions: 7.15.2.2.
+ * Extensible wide-character mapping functions: 7.15.3.2.
  */
 
-/* Construct value that describes a class of wide characters identified
-   by the string argument PROPERTY.  */
-extern wctype_t wctype (const char *__property) __THROW;
-
-/* Determine whether the wide-character WC has the property described by
-   DESC.  */
-extern int iswctype (wint_t __wc, wctype_t __desc) __THROW;
-
-
-/*
- * Wide-character case-mapping functions: 7.15.3.1.
- */
+__BEGIN_DECLS
 
 /* Scalar type that can hold values which represent locale-specific
    character mappings.  */
 typedef const __int32_t *wctrans_t;
 
-/* Converts an uppercase letter to the corresponding lowercase letter.  */
-extern wint_t towlower (wint_t __wc) __THROW;
-
-/* Converts an lowercase letter to the corresponding uppercase letter.  */
-extern wint_t towupper (wint_t __wc) __THROW;
-
-__END_DECLS
-
-#endif	/* need iswxxx.  */
-
-
-/* The remaining definitions and declarations must not appear in the
-   <wchar.h> header.  */
-#ifdef _WCTYPE_H
-
-/*
- * Extensible wide-character mapping functions: 7.15.3.2.
- */
-
-__BEGIN_DECLS
-
 /* Construct value that describes a mapping between wide characters
    identified by the string argument PROPERTY.  */
 extern wctrans_t wctrans (const char *__property) __THROW;
@@ -276,7 +122,6 @@ extern wctype_t wctype_l (const char *__property, __locale_t __locale)
 extern int iswctype_l (wint_t __wc, wctype_t __desc, __locale_t __locale)
      __THROW;
 
-
 /*
  * Wide-character case-mapping functions.
  */
@@ -300,6 +145,4 @@ extern wint_t towctrans_l (wint_t __wc, wctrans_t __desc,
 
 __END_DECLS
 
-#endif	/* __WCTYPE_H defined.  */
-
 #endif /* wctype.h  */