As someone who can remember when you might not be able to include both
string.h and strings.h at the same time, it annoys me that strings.h
still exists and is the only standard source for str(n)casecmp(_l) and
ffs.  I think it’s right that we expose those functions from string.h.
However, there’s no reason we need to keep exposing the other obsolete
functions that strings.h declares from string.h.

This patch creates <bits/strings_x2k8.h>, which declares the
non-obsolete functions whose official home is strings.h.  strings.h
includes it unconditionally, and string.h includes it under
__USE_MISC, instead of strings.h.

Two tests of the obsolete strings.h functions had to be adjusted.

	* string/strings.h (strcasecmp, strncasecmp, strcasecmp_l)
	(strncasecmp_l, ffs, ffsl, ffsll): Move declarations to...
	* string/bits/strings_x2k8.h: ... this new file.
	* string/Makefile: Install bits/strings_x2k8.h.
	* include/bits/strings_x2k8h: New wrapper.
	* string/string.h: Include bits/strings_x2k8.h instead of
	strings.h.

	* debug/tst-chk1.c, string/test-string.h: Include strings.h.
	* scripts/check-obsolete-constructs.py: string.h is no longer
	expected to include strings.h.

	* sysdeps/i386/i686/multiarch/bcopy.c
	* sysdeps/i386/i686/multiarch/bzero.c
	* sysdeps/i386/i686/multiarch/ifunc-impl-list.c
	* sysdeps/powerpc/powerpc32/power4/multiarch/ifunc-impl-list.c
	* sysdeps/powerpc/powerpc64/multiarch/bcopy-ppc64.c
	* sysdeps/powerpc/powerpc64/multiarch/bcopy.c
	* sysdeps/powerpc/powerpc64/multiarch/ifunc-impl-list.c
	* sysdeps/s390/bzero.c
	* sysdeps/s390/multiarch/ifunc-impl-list.c
	* sysdeps/sparc/sparc64/multiarch/bzero.c
	* sysdeps/sparc/sparc64/multiarch/ifunc-impl-list.c:
        Include strings.h.

With only two exceptions (sys/types.h and sys/param.h, both of which
historically might have defined BYTE_ORDER) the public headers that
include <endian.h> only want to be able to test __BYTE_ORDER against
__*_ENDIAN.

This patch creates a new bits/endian.h that can be included by any
header that wants to be able to test __BYTE_ORDER and/or
__FLOAT_WORD_ORDER against the __*_ENDIAN constants, or needs
__LONG_LONG_PAIR.  It only defines macros in the implementation
namespace.

The existing bits/endian.h (which could not be included independently
of endian.h, and only defines __BYTE_ORDER and maybe __FLOAT_WORD_ORDER)
is renamed to bits/endianness.h.  I also took the opportunity to
canonicalize the form of this header, which we are stuck with having
one copy of per architecture.  Since they are so short, this means git
doesn’t understand that they were renamed from existing headers, sigh.

endian.h itself is a nonstandard header and its only remaining use
from a standard header is guarded by __USE_MISC, so I dropped the
__USE_MISC conditionals from around all of the public-namespace things
it defines.  (This means, an application that requests strict library
conformance but includes endian.h will still see the definition of
BYTE_ORDER.)

A few changes to specific bits/endian(ness).h variants deserve
mention:

 - sysdeps/unix/sysv/linux/ia64/bits/endian.h is moved to
   sysdeps/ia64/bits/endianness.h.  If I remember correctly, ia64 did
   have selectable endianness, but we have assembly code in
   sysdeps/ia64 that assumes it’s little-endian, so there is no reason
   to treat the ia64 endianness.h as linux-specific.

 - The C-SKY port does not fully support big-endian mode, the compile
   will error out if __CSKYBE__ is defined.

 - The PowerPC port had extra logic in its bits/endian.h to detect a
   broken compiler, which strikes me as unnecessary, so I removed it.

 - The only files that defined __FLOAT_WORD_ORDER always defined it to
   the same value as __BYTE_ORDER, so I removed those definitions.
   The SH bits/endian(ness).h had comments inconsistent with the
   actual setting of __FLOAT_WORD_ORDER, which I also removed.

 - I *removed* copyright boilerplate from the few bits/endian(ness).h
   headers that had it; these files record a single fact in a fashion
   dictated by an external spec, so I do not think they are copyrightable.

As long as I was changing every copy of ieee754.h in the tree, I
noticed that only the MIPS variant includes float.h, because it uses
LDBL_MANT_DIG to decide among three different versions of
ieee854_long_double.  This patch makes it not include float.h when
GCC’s intrinsic __LDBL_MANT_DIG__ is available.

	* string/endian.h: Unconditionally define LITTLE_ENDIAN,
	BIG_ENDIAN, PDP_ENDIAN, and BYTE_ORDER.	 Condition byteswapping
	macros only on !__ASSEMBLER__.	Move the definitions of
	__BIG_ENDIAN, __LITTLE_ENDIAN, __PDP_ENDIAN, __FLOAT_WORD_ORDER,
	and __LONG_LONG_PAIR to...
	* string/bits/endian.h: ...this new file, which includes
	the renamed header bits/endianness.h for the definition of
	__BYTE_ORDER and possibly __FLOAT_WORD_ORDER.

	* string/Makefile: Install bits/endianness.h.
	* include/bits/endian.h: New wrapper.

	* bits/endian.h: Rename to bits/endianness.h.
	Add multiple-include guard.  Rewrite the comment explaining what
	the machine-specific variants of this file should do.

	* sysdeps/unix/sysv/linux/ia64/bits/endian.h:
	Move to sysdeps/ia64.

	* sysdeps/aarch64/bits/endian.h
	* sysdeps/alpha/bits/endian.h
	* sysdeps/arm/bits/endian.h
	* sysdeps/csky/bits/endian.h
	* sysdeps/hppa/bits/endian.h
	* sysdeps/ia64/bits/endian.h
	* sysdeps/m68k/bits/endian.h
	* sysdeps/microblaze/bits/endian.h
	* sysdeps/mips/bits/endian.h
	* sysdeps/nios2/bits/endian.h
	* sysdeps/powerpc/bits/endian.h
	* sysdeps/riscv/bits/endian.h
	* sysdeps/s390/bits/endian.h
	* sysdeps/sh/bits/endian.h
	* sysdeps/sparc/bits/endian.h
	* sysdeps/x86/bits/endian.h:
	Rename to endianness.h; canonicalize form of file; remove
	redundant definitions of __FLOAT_WORD_ORDER.

	* sysdeps/powerpc/bits/endianness.h: Remove logic to check for
	broken compilers.

	* ctype/ctype.h
	* sysdeps/aarch64/nptl/bits/pthreadtypes-arch.h
	* sysdeps/arm/nptl/bits/pthreadtypes-arch.h
	* sysdeps/csky/nptl/bits/pthreadtypes-arch.h
	* sysdeps/ia64/ieee754.h
	* sysdeps/ieee754/ieee754.h
	* sysdeps/ieee754/ldbl-128/ieee754.h
	* sysdeps/ieee754/ldbl-128ibm/ieee754.h
	* sysdeps/m68k/nptl/bits/pthreadtypes-arch.h
	* sysdeps/microblaze/nptl/bits/pthreadtypes-arch.h
	* sysdeps/mips/ieee754/ieee754.h
	* sysdeps/mips/nptl/bits/pthreadtypes-arch.h
	* sysdeps/nios2/nptl/bits/pthreadtypes-arch.h
	* sysdeps/nptl/pthread.h
	* sysdeps/riscv/nptl/bits/pthreadtypes-arch.h
	* sysdeps/sh/nptl/bits/pthreadtypes-arch.h
	* sysdeps/sparc/sparc32/ieee754.h
	* sysdeps/unix/sysv/linux/generic/bits/stat.h
	* sysdeps/unix/sysv/linux/generic/bits/statfs.h
	* sysdeps/unix/sysv/linux/sys/acct.h
	* wctype/bits/wctype-wchar.h:
	Include bits/endian.h, not endian.h.

	* sysdeps/unix/sysv/linux/hppa/pthread.h: Don’t include endian.h.

	* sysdeps/mips/ieee754/ieee754.h: Use __LDBL_MANT_DIG__
	in ifdefs, instead of LDBL_MANT_DIG.  Only include float.h
	when __LDBL_MANT_DIG__ is not predefined, in which case
	define __LDBL_MANT_DIG__ to equal LDBL_MANT_DIG.

Also, change sources.redhat.com to sourceware.org.
This patch was automatically generated by running the following shell
script, which uses GNU sed, and which avoids modifying files imported
from upstream:

sed -ri '
  s,(http|ftp)(://(.*\.)?(gnu|fsf|sourceware)\.org($|[^.]|\.[^a-z])),https\2,g
  s,(http|ftp)(://(.*\.)?)sources\.redhat\.com($|[^.]|\.[^a-z]),https\2sourceware.org\4,g
' \
  $(find $(git ls-files) -prune -type f \
      ! -name '*.po' \
      ! -name 'ChangeLog*' \
      ! -path COPYING ! -path COPYING.LIB \
      ! -path manual/fdl-1.3.texi ! -path manual/lgpl-2.1.texi \
      ! -path manual/texinfo.tex ! -path scripts/config.guess \
      ! -path scripts/config.sub ! -path scripts/install-sh \
      ! -path scripts/mkinstalldirs ! -path scripts/move-if-change \
      ! -path INSTALL ! -path  locale/programs/charmap-kw.h \
      ! -path po/libc.pot ! -path sysdeps/gnu/errlist.c \
      ! '(' -name configure \
            -execdir test -f configure.ac -o -f configure.in ';' ')' \
      ! '(' -name preconfigure \
            -execdir test -f preconfigure.ac ';' ')' \
      -print)

and then by running 'make dist-prepare' to regenerate files built
from the altered files, and then executing the following to cleanup:

  chmod a+x sysdeps/unix/sysv/linux/riscv/configure
  # Omit irrelevant whitespace and comment-only changes,
  # perhaps from a slightly-different Autoconf version.
  git checkout -f \
    sysdeps/csky/configure \
    sysdeps/hppa/configure \
    sysdeps/riscv/configure \
    sysdeps/unix/sysv/linux/csky/configure
  # Omit changes that caused a pre-commit check to fail like this:
  # remote: *** error: sysdeps/powerpc/powerpc64/ppc-mcount.S: trailing lines
  git checkout -f \
    sysdeps/powerpc/powerpc64/ppc-mcount.S \
    sysdeps/unix/sysv/linux/s390/s390-64/syscall.S
  # Omit change that caused a pre-commit check to fail like this:
  # remote: *** error: sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S: last line does not end in newline
  git checkout -f sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S

	* All files with FSF copyright notices: Update copyright dates
	using scripts/update-copyrights.
	* locale/programs/charmap-kw.h: Regenerated.
	* locale/programs/locfile-kw.h: Likewise.

	* All files with FSF copyright notices: Update copyright dates
	using scripts/update-copyrights.
	* locale/programs/charmap-kw.h: Regenerated.
	* locale/programs/locfile-kw.h: Likewise.

These machine-dependent inline string functions have never been on by
default, and even if they were a good idea at the time they were
introduced, they haven't really been touched in ten to fifteen years
and probably aren't a good idea on current-gen processors.  Current
thinking is that this class of optimization is best left to the
compiler.

	* bits/string.h, string/bits/string.h
	* sysdeps/aarch64/bits/string.h
	* sysdeps/m68k/m680x0/m68020/bits/string.h
	* sysdeps/s390/bits/string.h, sysdeps/sparc/bits/string.h
	* sysdeps/x86/bits/string.h: Delete file.

	* string/string.h: Don't include bits/string.h.
	* string/bits/string3.h: Rename to bits/string_fortified.h.
	No need to undef various symbols that the removed headers
	might have defined as macros.
	* string/Makefile (headers): Remove bits/string.h, change
	bits/string3.h to bits/string_fortified.h.
	* string/string-inlines.c: Update commentary.  Remove definitions
	of various macros that nothing looks at anymore.  Don't directly
	include bits/string.h. Set _STRING_INLINE_unaligned here, based on
	compiler-predefined macros.
	* string/strncat.c: If STRNCAT is not defined, or STRNCAT_PRIMARY
	_is_ defined, provide internal hidden alias __strncat.
	* include/string.h: Declare internal hidden alias __strncat.
	Only forward __stpcpy to __builtin_stpcpy if __NO_STRING_INLINES is
	not defined.
	* include/bits/string3.h: Rename to bits/string_fortified.h,
	update to match above.

	* sysdeps/i386/string-inlines.c: Define compat symbols for
	everything formerly defined by sysdeps/x86/bits/string.h.
	Make existing definitions into compat symbols as well.
	Remove some no-longer-necessary messing around with macros.

	* sysdeps/powerpc/powerpc32/power4/multiarch/mempcpy.c
	* sysdeps/powerpc/powerpc64/multiarch/mempcpy.c
	* sysdeps/powerpc/powerpc64/multiarch/stpcpy.c
	* sysdeps/s390/multiarch/mempcpy.c
	No need to define _HAVE_STRING_ARCH_mempcpy.
	Do define __NO_STRING_INLINES and NO_MEMPCPY_STPCPY_REDIRECT.

	* sysdeps/i386/i686/multiarch/strncat-c.c
	* sysdeps/s390/multiarch/strncat-c.c
	* sysdeps/x86_64/multiarch/strncat-c.c
	Define STRNCAT_PRIMARY.  Don't change definition of libc_hidden_def.

There is no longer a need for string2.h, so remove it and all mention of it.
Move the redirect for __stpcpy to include/string.h since it is still required
until all internal uses have been renamed.
This fixes several linknamespace/localplt failures when building with -Os.

	[BZ #15105]
	[BZ #19463]
	* include/string.h: Add internal redirect for __stpcpy.
	* string/Makefile: Remove bits/string2.h.
	* string/string.h: Update comment.
	* string/string-inlines.c: Remove bits/string2.h include and comment.
	* string/bits/string2.h: Remove file.

calls with constant strings shows a small (~10%) performance gain, strdup is
typically used in error reporting code, so not performance critical.
Remove the now unused __need_malloc_and_calloc related defines from stdlib.h.

Rename existing uses of str(n)dup to __str(n)dup so it no longer needs to be
redirected to a builtin.  Also building GLIBC with -Os now no longer shows
localplt or linkname space failures (partial fix for BZ #15105 and BZ #19463).

        [BZ #15105]
        [BZ #19463]
        * elf/dl-cache.c (_dl_load_cache_lookup): Use __strdup.
        * inet/rcmd.c (rcmd_af): Likewise.
        * inet/rexec.c   (rexec_af): Likewise.
        * intl/dcigettext.c (_LIBC): Likewise.
        * intl/finddomain.c (_nl_find_domain): Use strdup expansion.
        * locale/loadarchive.c (_nl_load_locale_from_archive): Use __strdup.
        * locale/setlocale.c (setlocale): Likewise.
        * posix/spawn_faction_addopen.c
        (posix_spawn_file_actions_addopen): Likewise.
        * stdlib/putenv.c (putenv): Use __strndup.
        * sunrpc/svc_simple.c (__registerrpc): Use __strdup.
        * sysdeps/posix/getaddrinfo.c (gaih_inet): Use __strdup/__strndup.
        * include/stdlib.h (__need_malloc_and_calloc): Remove uses.
        (__Need_M_And_C) Remove define/undef.
        * stdlib/stdlib.h (__need_malloc_and_calloc): Remove uses.
        (__malloc_and_calloc_defined): Remove define.
        * string/bits/string2.h (__strdup): Remove define.
        (strdup): Likewise.
        (__strndup): Likewise.
        (strndup): Likewise.

optimization seems unlikely to ever be useful, but if it occurs in
real code it should be added to GCC.  Expanding strcmp of small strings
does appear useful (benchmarking shows it is 2-3x faster), so this would
be useful to implement in GCC (PR 78809).

	* string/bits/string2.h (strcmp): Remove define.
	(__strcmp_cg): Likewise.
	(strncmp): Likewise.