diff --git a/NEWS b/NEWS
index 2a1a4bfd856..a5d4d252d21 100644
--- a/NEWS
+++ b/NEWS
@@ -110,6 +110,9 @@ Deprecated and removed features, and other changes affecting compatibility:
 
 * The tilepro-*-linux-gnu configuration is no longer supported.
 
+* The nonstandard header files <libio.h> and <_G_config.h> are deprecated
+  and will be removed in a future release.
+
 Changes to build and runtime requirements:
 
 * bison version 2.7 or later is required to generate code in the 'intl'
diff --git a/sysdeps/generic/_G_config.h b/bits/_G_config.h
similarity index 84%
rename from sysdeps/generic/_G_config.h
rename to bits/_G_config.h
index c49eed395b7..5310ce14667 100644
--- a/sysdeps/generic/_G_config.h
+++ b/bits/_G_config.h
@@ -1,8 +1,12 @@
 /* This file is needed by libio to define various configuration parameters.
    These are always the same in the GNU C library.  */
 
-#ifndef _G_config_h
-#define _G_config_h 1
+#ifndef _BITS_G_CONFIG_H
+#define _BITS_G_CONFIG_H 1
+
+#if !defined _BITS_LIBIO_H && !defined _G_CONFIG_H
+#error "Never include <bits/_G_config.h> directly; use <stdio.h> instead."
+#endif
 
 /* Define types for libio in terms of the standard internal type names.  */
 
@@ -55,4 +59,4 @@ typedef union
 
 #define _G_BUFSIZ 8192
 
-#endif	/* _G_config.h */
+#endif	/* bits/_G_config.h */
diff --git a/csu/init.c b/csu/init.c
index bb68386c9b0..c50bb35e65e 100644
--- a/csu/init.c
+++ b/csu/init.c
@@ -18,7 +18,7 @@
 
 #if defined __GNUC__ && __GNUC__ >= 2
 
-#include <_G_config.h>
+#include <stdio.h>
 
 /* This records which stdio is linked against in the application. */
 const int _IO_stdin_used = _G_IO_IO_FILE_VERSION;
diff --git a/include/libio.h b/include/bits/libio.h
similarity index 97%
rename from include/libio.h
rename to include/bits/libio.h
index d2fa7967586..572395d5ffb 100644
--- a/include/libio.h
+++ b/include/bits/libio.h
@@ -1,7 +1,7 @@
 #if !defined _ISOMAC && defined _IO_MTSAFE_IO
 # include <stdio-lock.h>
 #endif
-#include <libio/libio.h>
+#include <libio/bits/libio.h>
 
 #ifndef _ISOMAC
 #ifndef _LIBC_LIBIO_H
diff --git a/libio/Makefile b/libio/Makefile
index c75e0d8e50a..6eb03ab1fa8 100644
--- a/libio/Makefile
+++ b/libio/Makefile
@@ -22,7 +22,8 @@ subdir	:= libio
 
 include ../Makeconfig
 
-headers	:= stdio.h libio.h _G_config.h bits/stdio.h \
+headers	:= stdio.h libio.h _G_config.h \
+	   bits/stdio.h bits/libio.h bits/_G_config.h \
 	   bits/sys_errlist.h bits/stdio2.h bits/stdio-ldbl.h bits/libio-ldbl.h \
 	   bits/types/FILE.h bits/types/__FILE.h
 
diff --git a/libio/_G_config.h b/libio/_G_config.h
new file mode 100644
index 00000000000..a0d70f6f0cc
--- /dev/null
+++ b/libio/_G_config.h
@@ -0,0 +1,25 @@
+/* Copyright (C) 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 _G_CONFIG_H
+#define _G_CONFIG_H 1
+
+#warning "<_G_config.h> is deprecated; use <stdio.h> instead."
+
+#include <bits/_G_config.h>
+
+#endif
diff --git a/libio/libio.h b/libio/bits/libio.h
similarity index 98%
copy from libio/libio.h
copy to libio/bits/libio.h
index 14bcb92332c..eb518b95d80 100644
--- a/libio/libio.h
+++ b/libio/bits/libio.h
@@ -25,10 +25,14 @@
    This exception applies to code released by its copyright holders
    in files containing the exception.  */
 
-#ifndef _IO_STDIO_H
-#define _IO_STDIO_H
+#ifndef _BITS_LIBIO_H
+#define _BITS_LIBIO_H 1
 
-#include <_G_config.h>
+#if !defined _STDIO_H && !defined _LIBIO_H
+#error "Never include <bits/libio.h> directly; use <stdio.h> instead."
+#endif
+
+#include <bits/_G_config.h>
 /* ALL of these should be defined in _G_config.h */
 #define _IO_fpos_t _G_fpos_t
 #define _IO_fpos64_t _G_fpos64_t
@@ -520,4 +524,4 @@ extern void _IO_free_wbackup_area (_IO_FILE *) __THROW;
 }
 #endif
 
-#endif /* _IO_STDIO_H */
+#endif /* _BITS_LIBIO_H */
diff --git a/libio/fmemopen.c b/libio/fmemopen.c
index 0b45f9c3237..dbc663b48c0 100644
--- a/libio/fmemopen.c
+++ b/libio/fmemopen.c
@@ -22,7 +22,6 @@
 
 
 #include <errno.h>
-#include <libio.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <stdint.h>
diff --git a/libio/iofgetpos.c b/libio/iofgetpos.c
index f3034528f14..524183afd32 100644
--- a/libio/iofgetpos.c
+++ b/libio/iofgetpos.c
@@ -29,11 +29,13 @@
    complain about the mismatch when we do the alias below.  */
 #define _IO_new_fgetpos64 __renamed__IO_new_fgetpos64
 #define _IO_fgetpos64 __renamed__IO_fgetpos64
+#define fgetpos64 __renamed_fgetpos64
 
 #include "libioP.h"
 
 #undef _IO_new_fgetpos64
 #undef _IO_fgetpos64
+#undef fgetpos64
 
 #include <errno.h>
 #include <stdlib.h>
diff --git a/libio/iofsetpos.c b/libio/iofsetpos.c
index 1a71867e59b..a80d3e1c231 100644
--- a/libio/iofsetpos.c
+++ b/libio/iofsetpos.c
@@ -29,11 +29,13 @@
    complain about the mismatch when we do the alias below.  */
 #define _IO_new_fsetpos64 __renamed__IO_new_fsetpos64
 #define _IO_fsetpos64 __renamed__IO_fsetpos64
+#define fsetpos64 __renamed_fsetpos64
 
 #include <libioP.h>
 
 #undef _IO_new_fsetpos64
 #undef _IO_fsetpos64
+#undef fsetpos64
 
 #include <errno.h>
 #include <shlib-compat.h>
diff --git a/libio/iolibio.h b/libio/iolibio.h
index 0185e685d4d..621b31cff1f 100644
--- a/libio/iolibio.h
+++ b/libio/iolibio.h
@@ -1,4 +1,4 @@
-#include <libio.h>
+#include <stdio.h>
 
 /* These emulate stdio functionality, but with a different name
    (_IO_ungetc instead of ungetc), and using _IO_FILE instead of FILE. */
diff --git a/libio/libio.h b/libio/libio.h
index 14bcb92332c..6abea01f45d 100644
--- a/libio/libio.h
+++ b/libio/libio.h
@@ -1,6 +1,5 @@
-/* Copyright (C) 1991-2017 Free Software Foundation, Inc.
+/* Copyright (C) 2017 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
-   Written by Per Bothner <bothner@cygnus.com>.
 
    The GNU C Library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
@@ -14,510 +13,13 @@
 
    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/>.
+   <http://www.gnu.org/licenses/>.  */
 
-   As a special exception, if you link the code in this file with
-   files compiled with a GNU compiler to produce an executable,
-   that does not cause the resulting executable to be covered by
-   the GNU Lesser General Public License.  This exception does not
-   however invalidate any other reasons why the executable file
-   might be covered by the GNU Lesser General Public License.
-   This exception applies to code released by its copyright holders
-   in files containing the exception.  */
+#ifndef _LIBIO_H
+#define _LIBIO_H 1
 
-#ifndef _IO_STDIO_H
-#define _IO_STDIO_H
+#warning "<libio.h> is deprecated; use <stdio.h> instead."
 
-#include <_G_config.h>
-/* ALL of these should be defined in _G_config.h */
-#define _IO_fpos_t _G_fpos_t
-#define _IO_fpos64_t _G_fpos64_t
-#define _IO_size_t size_t
-#define _IO_ssize_t __ssize_t
-#define _IO_off_t __off_t
-#define _IO_off64_t __off64_t
-#define _IO_pid_t __pid_t
-#define _IO_uid_t __uid_t
-#define _IO_iconv_t _G_iconv_t
-#define _IO_HAVE_ST_BLKSIZE _G_HAVE_ST_BLKSIZE
-#define _IO_BUFSIZ _G_BUFSIZ
-#define _IO_va_list _G_va_list
-#define _IO_wint_t wint_t
+#include <bits/libio.h>
 
-/* This define avoids name pollution if we're using GNU stdarg.h */
-#define __need___va_list
-#include <stdarg.h>
-#ifdef __GNUC_VA_LIST
-# undef _IO_va_list
-# define _IO_va_list __gnuc_va_list
-#endif /* __GNUC_VA_LIST */
-
-#ifndef __P
-# include <sys/cdefs.h>
-#endif /*!__P*/
-
-#define _IO_UNIFIED_JUMPTABLES 1
-
-#ifndef EOF
-# define EOF (-1)
-#endif
-#ifndef NULL
-# if defined __GNUG__ && \
-    (__GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 8))
-#  define NULL (__null)
-# else
-#  if !defined(__cplusplus)
-#   define NULL ((void*)0)
-#  else
-#   define NULL (0)
-#  endif
-# endif
-#endif
-
-#define _IOS_INPUT	1
-#define _IOS_OUTPUT	2
-#define _IOS_ATEND	4
-#define _IOS_APPEND	8
-#define _IOS_TRUNC	16
-#define _IOS_NOCREATE	32
-#define _IOS_NOREPLACE	64
-#define _IOS_BIN	128
-
-/* Magic numbers and bits for the _flags field.
-   The magic numbers use the high-order bits of _flags;
-   the remaining bits are available for variable flags.
-   Note: The magic numbers must all be negative if stdio
-   emulation is desired. */
-
-#define _IO_MAGIC 0xFBAD0000 /* Magic number */
-#define _OLD_STDIO_MAGIC 0xFABC0000 /* Emulate old stdio. */
-#define _IO_MAGIC_MASK 0xFFFF0000
-#define _IO_USER_BUF 1 /* User owns buffer; don't delete it on close. */
-#define _IO_UNBUFFERED 2
-#define _IO_NO_READS 4 /* Reading not allowed */
-#define _IO_NO_WRITES 8 /* Writing not allowd */
-#define _IO_EOF_SEEN 0x10
-#define _IO_ERR_SEEN 0x20
-#define _IO_DELETE_DONT_CLOSE 0x40 /* Don't call close(_fileno) on cleanup. */
-#define _IO_LINKED 0x80 /* Set if linked (using _chain) to streambuf::_list_all.*/
-#define _IO_IN_BACKUP 0x100
-#define _IO_LINE_BUF 0x200
-#define _IO_TIED_PUT_GET 0x400 /* Set if put and get pointer logicly tied. */
-#define _IO_CURRENTLY_PUTTING 0x800
-#define _IO_IS_APPENDING 0x1000
-#define _IO_IS_FILEBUF 0x2000
-#define _IO_BAD_SEEN 0x4000
-#define _IO_USER_LOCK 0x8000
-
-#define _IO_FLAGS2_MMAP 1
-#define _IO_FLAGS2_NOTCANCEL 2
-#ifdef _LIBC
-# define _IO_FLAGS2_FORTIFY 4
-#endif
-#define _IO_FLAGS2_USER_WBUF 8
-#ifdef _LIBC
-# define _IO_FLAGS2_SCANF_STD 16
-# define _IO_FLAGS2_NOCLOSE 32
-# define _IO_FLAGS2_CLOEXEC 64
-# define _IO_FLAGS2_NEED_LOCK 128
-#endif
-
-/* These are "formatting flags" matching the iostream fmtflags enum values. */
-#define _IO_SKIPWS 01
-#define _IO_LEFT 02
-#define _IO_RIGHT 04
-#define _IO_INTERNAL 010
-#define _IO_DEC 020
-#define _IO_OCT 040
-#define _IO_HEX 0100
-#define _IO_SHOWBASE 0200
-#define _IO_SHOWPOINT 0400
-#define _IO_UPPERCASE 01000
-#define _IO_SHOWPOS 02000
-#define _IO_SCIENTIFIC 04000
-#define _IO_FIXED 010000
-#define _IO_UNITBUF 020000
-#define _IO_STDIO 040000
-#define _IO_DONT_CLOSE 0100000
-#define _IO_BOOLALPHA 0200000
-
-
-struct _IO_jump_t;  struct _IO_FILE;
-
-/* During the build of glibc itself, _IO_lock_t will already have been
-   defined by internal headers.  */
-#ifndef _IO_lock_t_defined
-typedef void _IO_lock_t;
-#endif
-
-
-/* A streammarker remembers a position in a buffer. */
-
-struct _IO_marker {
-  struct _IO_marker *_next;
-  struct _IO_FILE *_sbuf;
-  /* If _pos >= 0
- it points to _buf->Gbase()+_pos. FIXME comment */
-  /* if _pos < 0, it points to _buf->eBptr()+_pos. FIXME comment */
-  int _pos;
-#if 0
-    void set_streampos(streampos sp) { _spos = sp; }
-    void set_offset(int offset) { _pos = offset; _spos = (streampos)(-2); }
-  public:
-    streammarker(streambuf *sb);
-    ~streammarker();
-    int saving() { return  _spos == -2; }
-    int delta(streammarker&);
-    int delta();
-#endif
-};
-
-/* This is the structure from the libstdc++ codecvt class.  */
-enum __codecvt_result
-{
-  __codecvt_ok,
-  __codecvt_partial,
-  __codecvt_error,
-  __codecvt_noconv
-};
-
-#if defined _LIBC || defined _GLIBCPP_USE_WCHAR_T
-/* The order of the elements in the following struct must match the order
-   of the virtual functions in the libstdc++ codecvt class.  */
-struct _IO_codecvt
-{
-  void (*__codecvt_destr) (struct _IO_codecvt *);
-  enum __codecvt_result (*__codecvt_do_out) (struct _IO_codecvt *,
-					     __mbstate_t *,
-					     const wchar_t *,
-					     const wchar_t *,
-					     const wchar_t **, char *,
-					     char *, char **);
-  enum __codecvt_result (*__codecvt_do_unshift) (struct _IO_codecvt *,
-						 __mbstate_t *, char *,
-						 char *, char **);
-  enum __codecvt_result (*__codecvt_do_in) (struct _IO_codecvt *,
-					    __mbstate_t *,
-					    const char *, const char *,
-					    const char **, wchar_t *,
-					    wchar_t *, wchar_t **);
-  int (*__codecvt_do_encoding) (struct _IO_codecvt *);
-  int (*__codecvt_do_always_noconv) (struct _IO_codecvt *);
-  int (*__codecvt_do_length) (struct _IO_codecvt *, __mbstate_t *,
-			      const char *, const char *, _IO_size_t);
-  int (*__codecvt_do_max_length) (struct _IO_codecvt *);
-
-  _IO_iconv_t __cd_in;
-  _IO_iconv_t __cd_out;
-};
-
-/* Extra data for wide character streams.  */
-struct _IO_wide_data
-{
-  wchar_t *_IO_read_ptr;	/* Current read pointer */
-  wchar_t *_IO_read_end;	/* End of get area. */
-  wchar_t *_IO_read_base;	/* Start of putback+get area. */
-  wchar_t *_IO_write_base;	/* Start of put area. */
-  wchar_t *_IO_write_ptr;	/* Current put pointer. */
-  wchar_t *_IO_write_end;	/* End of put area. */
-  wchar_t *_IO_buf_base;	/* Start of reserve area. */
-  wchar_t *_IO_buf_end;		/* End of reserve area. */
-  /* The following fields are used to support backing up and undo. */
-  wchar_t *_IO_save_base;	/* Pointer to start of non-current get area. */
-  wchar_t *_IO_backup_base;	/* Pointer to first valid character of
-				   backup area */
-  wchar_t *_IO_save_end;	/* Pointer to end of non-current get area. */
-
-  __mbstate_t _IO_state;
-  __mbstate_t _IO_last_state;
-  struct _IO_codecvt _codecvt;
-
-  wchar_t _shortbuf[1];
-
-  const struct _IO_jump_t *_wide_vtable;
-};
-#endif
-
-struct _IO_FILE {
-  int _flags;		/* High-order word is _IO_MAGIC; rest is flags. */
-#define _IO_file_flags _flags
-
-  /* The following pointers correspond to the C++ streambuf protocol. */
-  /* Note:  Tk uses the _IO_read_ptr and _IO_read_end fields directly. */
-  char* _IO_read_ptr;	/* Current read pointer */
-  char* _IO_read_end;	/* End of get area. */
-  char* _IO_read_base;	/* Start of putback+get area. */
-  char* _IO_write_base;	/* Start of put area. */
-  char* _IO_write_ptr;	/* Current put pointer. */
-  char* _IO_write_end;	/* End of put area. */
-  char* _IO_buf_base;	/* Start of reserve area. */
-  char* _IO_buf_end;	/* End of reserve area. */
-  /* The following fields are used to support backing up and undo. */
-  char *_IO_save_base; /* Pointer to start of non-current get area. */
-  char *_IO_backup_base;  /* Pointer to first valid character of backup area */
-  char *_IO_save_end; /* Pointer to end of non-current get area. */
-
-  struct _IO_marker *_markers;
-
-  struct _IO_FILE *_chain;
-
-  int _fileno;
-#if 0
-  int _blksize;
-#else
-  int _flags2;
-#endif
-  _IO_off_t _old_offset; /* This used to be _offset but it's too small.  */
-
-#define __HAVE_COLUMN /* temporary */
-  /* 1+column number of pbase(); 0 is unknown. */
-  unsigned short _cur_column;
-  signed char _vtable_offset;
-  char _shortbuf[1];
-
-  /*  char* _save_gptr;  char* _save_egptr; */
-
-  _IO_lock_t *_lock;
-#ifdef _IO_USE_OLD_IO_FILE
-};
-
-struct _IO_FILE_complete
-{
-  struct _IO_FILE _file;
-#endif
-#if defined _G_IO_IO_FILE_VERSION && _G_IO_IO_FILE_VERSION == 0x20001
-  _IO_off64_t _offset;
-# if defined _LIBC || defined _GLIBCPP_USE_WCHAR_T
-  /* Wide character stream stuff.  */
-  struct _IO_codecvt *_codecvt;
-  struct _IO_wide_data *_wide_data;
-  struct _IO_FILE *_freeres_list;
-  void *_freeres_buf;
-# else
-  void *__pad1;
-  void *__pad2;
-  void *__pad3;
-  void *__pad4;
-# endif
-  size_t __pad5;
-  int _mode;
-  /* Make sure we don't get into trouble again.  */
-  char _unused2[15 * sizeof (int) - 4 * sizeof (void *) - sizeof (size_t)];
-#endif
-};
-
-#ifndef __cplusplus
-typedef struct _IO_FILE _IO_FILE;
-#endif
-
-struct _IO_FILE_plus;
-
-extern struct _IO_FILE_plus _IO_2_1_stdin_;
-extern struct _IO_FILE_plus _IO_2_1_stdout_;
-extern struct _IO_FILE_plus _IO_2_1_stderr_;
-#ifndef _LIBC
-#define _IO_stdin ((_IO_FILE*)(&_IO_2_1_stdin_))
-#define _IO_stdout ((_IO_FILE*)(&_IO_2_1_stdout_))
-#define _IO_stderr ((_IO_FILE*)(&_IO_2_1_stderr_))
-#else
-extern _IO_FILE *_IO_stdin attribute_hidden;
-extern _IO_FILE *_IO_stdout attribute_hidden;
-extern _IO_FILE *_IO_stderr attribute_hidden;
-#endif
-
-
-/* Functions to do I/O and file management for a stream.  */
-
-/* Read NBYTES bytes from COOKIE into a buffer pointed to by BUF.
-   Return number of bytes read.  */
-typedef __ssize_t __io_read_fn (void *__cookie, char *__buf, size_t __nbytes);
-
-/* Write N bytes pointed to by BUF to COOKIE.  Write all N bytes
-   unless there is an error.  Return number of bytes written.  If
-   there is an error, return 0 and do not write anything.  If the file
-   has been opened for append (__mode.__append set), then set the file
-   pointer to the end of the file and then do the write; if not, just
-   write at the current file pointer.  */
-typedef __ssize_t __io_write_fn (void *__cookie, const char *__buf,
-				 size_t __n);
-
-/* Move COOKIE's file position to *POS bytes from the
-   beginning of the file (if W is SEEK_SET),
-   the current position (if W is SEEK_CUR),
-   or the end of the file (if W is SEEK_END).
-   Set *POS to the new file position.
-   Returns zero if successful, nonzero if not.  */
-typedef int __io_seek_fn (void *__cookie, _IO_off64_t *__pos, int __w);
-
-/* Close COOKIE.  */
-typedef int __io_close_fn (void *__cookie);
-
-
-#ifdef __USE_GNU
-/* User-visible names for the above.  */
-typedef __io_read_fn cookie_read_function_t;
-typedef __io_write_fn cookie_write_function_t;
-typedef __io_seek_fn cookie_seek_function_t;
-typedef __io_close_fn cookie_close_function_t;
-
-/* The structure with the cookie function pointers.  */
-typedef struct
-{
-  __io_read_fn *read;		/* Read bytes.  */
-  __io_write_fn *write;		/* Write bytes.  */
-  __io_seek_fn *seek;		/* Seek/tell file position.  */
-  __io_close_fn *close;		/* Close file.  */
-} _IO_cookie_io_functions_t;
-typedef _IO_cookie_io_functions_t cookie_io_functions_t;
-
-struct _IO_cookie_file;
-
-/* Initialize one of those.  */
-extern void _IO_cookie_init (struct _IO_cookie_file *__cfile, int __read_write,
-			     void *__cookie, _IO_cookie_io_functions_t __fns);
-#endif
-
-
-#ifdef __cplusplus
-extern "C" {
 #endif
-
-extern int __underflow (_IO_FILE *);
-extern int __uflow (_IO_FILE *);
-extern int __overflow (_IO_FILE *, int);
-#if defined _LIBC || defined _GLIBCPP_USE_WCHAR_T
-extern _IO_wint_t __wunderflow (_IO_FILE *);
-extern _IO_wint_t __wuflow (_IO_FILE *);
-extern _IO_wint_t __woverflow (_IO_FILE *, _IO_wint_t);
-#endif
-
-#if  __GNUC__ >= 3
-# define _IO_BE(expr, res) __builtin_expect ((expr), res)
-#else
-# define _IO_BE(expr, res) (expr)
-#endif
-
-#define _IO_getc_unlocked(_fp) \
-       (_IO_BE ((_fp)->_IO_read_ptr >= (_fp)->_IO_read_end, 0) \
-	? __uflow (_fp) : *(unsigned char *) (_fp)->_IO_read_ptr++)
-#define _IO_peekc_unlocked(_fp) \
-       (_IO_BE ((_fp)->_IO_read_ptr >= (_fp)->_IO_read_end, 0) \
-	  && __underflow (_fp) == EOF ? EOF \
-	: *(unsigned char *) (_fp)->_IO_read_ptr)
-#define _IO_putc_unlocked(_ch, _fp) \
-   (_IO_BE ((_fp)->_IO_write_ptr >= (_fp)->_IO_write_end, 0) \
-    ? __overflow (_fp, (unsigned char) (_ch)) \
-    : (unsigned char) (*(_fp)->_IO_write_ptr++ = (_ch)))
-
-#if defined _LIBC || defined _GLIBCPP_USE_WCHAR_T
-# define _IO_getwc_unlocked(_fp) \
-  (_IO_BE ((_fp)->_wide_data == NULL					\
-	   || ((_fp)->_wide_data->_IO_read_ptr				\
-	       >= (_fp)->_wide_data->_IO_read_end), 0)			\
-   ? __wuflow (_fp) : (_IO_wint_t) *(_fp)->_wide_data->_IO_read_ptr++)
-# define _IO_putwc_unlocked(_wch, _fp) \
-  (_IO_BE ((_fp)->_wide_data == NULL					\
-	   || ((_fp)->_wide_data->_IO_write_ptr				\
-	       >= (_fp)->_wide_data->_IO_write_end), 0)			\
-   ? __woverflow (_fp, _wch)						\
-   : (_IO_wint_t) (*(_fp)->_wide_data->_IO_write_ptr++ = (_wch)))
-#endif
-
-#define _IO_feof_unlocked(__fp) (((__fp)->_flags & _IO_EOF_SEEN) != 0)
-#define _IO_ferror_unlocked(__fp) (((__fp)->_flags & _IO_ERR_SEEN) != 0)
-
-extern int _IO_getc (_IO_FILE *__fp);
-extern int _IO_putc (int __c, _IO_FILE *__fp);
-extern int _IO_feof (_IO_FILE *__fp) __THROW;
-extern int _IO_ferror (_IO_FILE *__fp) __THROW;
-
-extern int _IO_peekc_locked (_IO_FILE *__fp);
-
-/* This one is for Emacs. */
-#define _IO_PENDING_OUTPUT_COUNT(_fp)	\
-	((_fp)->_IO_write_ptr - (_fp)->_IO_write_base)
-
-extern void _IO_flockfile (_IO_FILE *) __THROW;
-extern void _IO_funlockfile (_IO_FILE *) __THROW;
-extern int _IO_ftrylockfile (_IO_FILE *) __THROW;
-
-#define _IO_peekc(_fp) _IO_peekc_unlocked (_fp)
-#define _IO_flockfile(_fp) /**/
-#define _IO_funlockfile(_fp) /**/
-#define _IO_ftrylockfile(_fp) /**/
-#ifndef _IO_cleanup_region_start
-#define _IO_cleanup_region_start(_fct, _fp) /**/
-#endif
-#ifndef _IO_cleanup_region_end
-#define _IO_cleanup_region_end(_Doit) /**/
-#endif
-
-#define _IO_need_lock(_fp) \
-  (((_fp)->_flags2 & _IO_FLAGS2_NEED_LOCK) != 0)
-
-extern int _IO_vfscanf (_IO_FILE * __restrict, const char * __restrict,
-			_IO_va_list, int *__restrict);
-extern int _IO_vfprintf (_IO_FILE *__restrict, const char *__restrict,
-			 _IO_va_list);
-extern _IO_ssize_t _IO_padn (_IO_FILE *, int, _IO_ssize_t);
-extern _IO_size_t _IO_sgetn (_IO_FILE *, void *, _IO_size_t);
-
-extern _IO_off64_t _IO_seekoff (_IO_FILE *, _IO_off64_t, int, int);
-extern _IO_off64_t _IO_seekpos (_IO_FILE *, _IO_off64_t, int);
-
-extern void _IO_free_backup_area (_IO_FILE *) __THROW;
-
-#if defined _LIBC || defined _GLIBCPP_USE_WCHAR_T
-extern _IO_wint_t _IO_getwc (_IO_FILE *__fp);
-extern _IO_wint_t _IO_putwc (wchar_t __wc, _IO_FILE *__fp);
-extern int _IO_fwide (_IO_FILE *__fp, int __mode) __THROW;
-# if __GNUC__ >= 2
-/* While compiling glibc we have to handle compatibility with very old
-   versions.  */
-#  if defined _LIBC && defined SHARED
-#   include <shlib-compat.h>
-#   if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_1)
-#    define _IO_fwide_maybe_incompatible \
-  (__builtin_expect (&_IO_stdin_used == NULL, 0))
-extern const int _IO_stdin_used;
-weak_extern (_IO_stdin_used);
-#   endif
-#  endif
-#  ifndef _IO_fwide_maybe_incompatible
-#   define _IO_fwide_maybe_incompatible (0)
-#  endif
-/* A special optimized version of the function above.  It optimizes the
-   case of initializing an unoriented byte stream.  */
-#  define _IO_fwide(__fp, __mode) \
-  ({ int __result = (__mode);						      \
-     if (__result < 0 && ! _IO_fwide_maybe_incompatible)		      \
-       {								      \
-	 if ((__fp)->_mode == 0)					      \
-	   /* We know that all we have to do is to set the flag.  */	      \
-	   (__fp)->_mode = -1;						      \
-	 __result = (__fp)->_mode;					      \
-       }								      \
-     else if (__builtin_constant_p (__mode) && (__mode) == 0)		      \
-       __result = _IO_fwide_maybe_incompatible ? -1 : (__fp)->_mode;	      \
-     else								      \
-       __result = _IO_fwide (__fp, __result);				      \
-     __result; })
-# endif
-
-extern int _IO_vfwscanf (_IO_FILE * __restrict, const wchar_t * __restrict,
-			 _IO_va_list, int *__restrict);
-extern int _IO_vfwprintf (_IO_FILE *__restrict, const wchar_t *__restrict,
-			  _IO_va_list);
-extern _IO_ssize_t _IO_wpadn (_IO_FILE *, wint_t, _IO_ssize_t);
-extern void _IO_free_wbackup_area (_IO_FILE *) __THROW;
-#endif
-
-#ifdef __LDBL_COMPAT
-# include <bits/libio-ldbl.h>
-#endif
-
-#ifdef __cplusplus
-}
-#endif
-
-#endif /* _IO_STDIO_H */
diff --git a/libio/oldfmemopen.c b/libio/oldfmemopen.c
index c2fef8d9428..aeea2969d95 100644
--- a/libio/oldfmemopen.c
+++ b/libio/oldfmemopen.c
@@ -71,7 +71,6 @@
 #if SHLIB_COMPAT (libc, GLIBC_2_2, GLIBC_2_22)
 
 #include <errno.h>
-#include <libio.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <stdint.h>
diff --git a/libio/stdio.h b/libio/stdio.h
index 47490c8299d..6798cf1afb0 100644
--- a/libio/stdio.h
+++ b/libio/stdio.h
@@ -38,7 +38,7 @@ __BEGIN_DECLS
 
 #define _STDIO_USES_IOSTREAM
 
-#include <libio.h>
+#include <bits/libio.h>
 
 #if defined __USE_XOPEN || defined __USE_XOPEN2K8
 # ifdef __GNUC__
diff --git a/libio/strfile.h b/libio/strfile.h
index 74bd4eb269e..494526b1420 100644
--- a/libio/strfile.h
+++ b/libio/strfile.h
@@ -24,10 +24,7 @@
    This exception applies to code released by its copyright holders
    in files containing the exception.  */
 
-#include <libio.h>
-#ifdef TODO
-Merge into  libio.h ?
-#endif
+#include <stdio.h>
 
 typedef void *(*_IO_alloc_type) (_IO_size_t);
 typedef void (*_IO_free_type) (void*);
diff --git a/scripts/check-installed-headers.sh b/scripts/check-installed-headers.sh
index 4cbef0ea49f..a5e37c32297 100644
--- a/scripts/check-installed-headers.sh
+++ b/scripts/check-installed-headers.sh
@@ -84,6 +84,11 @@ for header in "$@"; do
         (sys/elf.h)
             continue;;
 
+        # libio.h and _G_config.h are deprecation stubs containing #warnings
+        # to use stdio.h instead.
+        (libio.h | _G_config.h)
+            continue;;
+
 	# sys/sysctl.h is unsupported for x32.
 	(sys/sysctl.h)
             case "$is_x32" in
diff --git a/stdio-common/vfscanf.c b/stdio-common/vfscanf.c
index 7d9d17bd84f..5bfbc37ad93 100644
--- a/stdio-common/vfscanf.c
+++ b/stdio-common/vfscanf.c
@@ -72,7 +72,6 @@
 
 #include <locale/localeinfo.h>
 #include <libioP.h>
-#include <libio.h>
 
 #undef va_list
 #define va_list	_IO_va_list
diff --git a/sysdeps/pthread/flockfile.c b/sysdeps/pthread/flockfile.c
index a8e6c28ed94..14c1be1d800 100644
--- a/sysdeps/pthread/flockfile.c
+++ b/sysdeps/pthread/flockfile.c
@@ -18,7 +18,6 @@
 
 #include <pthread.h>
 #include <stdio.h>
-#include <libio.h>
 #include <stdio-lock.h>
 
 
diff --git a/sysdeps/pthread/funlockfile.c b/sysdeps/pthread/funlockfile.c
index 2389ad4fbfa..9f5463448f6 100644
--- a/sysdeps/pthread/funlockfile.c
+++ b/sysdeps/pthread/funlockfile.c
@@ -18,7 +18,6 @@
 
 #include <pthread.h>
 #include <stdio.h>
-#include <libio.h>
 #include <stdio-lock.h>
 
 
diff --git a/sysdeps/unix/sysv/linux/_G_config.h b/sysdeps/unix/sysv/linux/bits/_G_config.h
similarity index 84%
rename from sysdeps/unix/sysv/linux/_G_config.h
rename to sysdeps/unix/sysv/linux/bits/_G_config.h
index 3bc6cfd5954..b390ec4246c 100644
--- a/sysdeps/unix/sysv/linux/_G_config.h
+++ b/sysdeps/unix/sysv/linux/bits/_G_config.h
@@ -1,8 +1,12 @@
 /* This file is needed by libio to define various configuration parameters.
    These are always the same in the GNU C library.  */
 
-#ifndef _G_config_h
-#define _G_config_h 1
+#ifndef _BITS_G_CONFIG_H
+#define _BITS_G_CONFIG_H 1
+
+#if !defined _BITS_LIBIO_H && !defined _G_CONFIG_H
+#error "Never include <bits/_G_config.h> directly; use <stdio.h> instead."
+#endif
 
 /* Define types for libio in terms of the standard internal type names.  */
 
@@ -56,4 +60,4 @@ typedef union
 
 #define _G_BUFSIZ 8192
 
-#endif	/* _G_config.h */
+#endif	/* bits/_G_config.h */
