[ This is my third attempt to add this configure option.  The first
version was approved but it came too late in the development cycle.
The second version was also approved, but I had to revert it:
<https://gcc.gnu.org/pipermail/gcc-patches/2022-November/607082.html>.
I've fixed the problem (by moving $(PICFLAG) from INTERNAL_CFLAGS to
ALL_COMPILERFLAGS).  Another change is that since r13-4536 I no longer
need to touch Makefile.def, so this patch is simplified. ]

This patch implements the --enable-host-pie configure option which
makes the compiler executables PIE.  This can be used to enhance
protection against ROP attacks, and can be viewed as part of a wider
trend to harden binaries.

It is similar to the option --enable-host-shared, except that --e-h-s
won't add -shared to the linker flags whereas --e-h-p will add -pie.
It is different from --enable-default-pie because that option just
adds an implicit -fPIE/-pie when the compiler is invoked, but the
compiler itself isn't PIE.

Since r12-5768-gfe7c3ecf, PCH works well with PIE, so there are no PCH
regressions.

When building the compiler, the build process may use various in-tree
libraries; these need to be built with -fPIE so that it's possible to
use them when building a PIE.  For instance, when --with-included-gettext
is in effect, intl object files must be compiled with -fPIE.  Similarly,
when building in-tree gmp, isl, mpfr and mpc, they must be compiled with
-fPIE.

With this patch and --enable-host-pie used to configure gcc:

$ file gcc/cc1{,plus,obj,gm2} gcc/f951 gcc/lto1 gcc/cpp gcc/go1 gcc/rust1 gcc/gnat1
gcc/cc1:     ELF 64-bit LSB pie executable, x86-64, version 1 (GNU/Linux), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, BuildID[sha1]=98e22cde129d304aa6f33e61b1c39e144aeb135e, for GNU/Linux 3.2.0, with debug_info, not stripped
gcc/cc1plus: ELF 64-bit LSB pie executable, x86-64, version 1 (GNU/Linux), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, BuildID[sha1]=859d1ea37e43dfe50c18fd4e3dd9a34bb1db8f77, for GNU/Linux 3.2.0, with debug_info, not stripped
gcc/cc1obj:  ELF 64-bit LSB pie executable, x86-64, version 1 (GNU/Linux), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, BuildID[sha1]=1964f8ecee6163182bc26134e2ac1f324816e434, for GNU/Linux 3.2.0, with debug_info, not stripped
gcc/cc1gm2:  ELF 64-bit LSB pie executable, x86-64, version 1 (GNU/Linux), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, BuildID[sha1]=a396672c7ff913d21855829202e7b02ecf42ff4c, for GNU/Linux 3.2.0, with debug_info, not stripped
gcc/f951:    ELF 64-bit LSB pie executable, x86-64, version 1 (GNU/Linux), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, BuildID[sha1]=59c523db893186547ac75c7a71f48be0a461c06b, for GNU/Linux 3.2.0, with debug_info, not stripped
gcc/lto1:    ELF 64-bit LSB pie executable, x86-64, version 1 (GNU/Linux), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, BuildID[sha1]=084a7b77df7be2d63c2d4c655b5bbc3fcdb6038d, for GNU/Linux 3.2.0, with debug_info, not stripped
gcc/cpp:     ELF 64-bit LSB pie executable, x86-64, version 1 (GNU/Linux), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, BuildID[sha1]=3503bf8390d219a10d6653b8560aa21158132168, for GNU/Linux 3.2.0, with debug_info, not stripped
gcc/go1:     ELF 64-bit LSB pie executable, x86-64, version 1 (GNU/Linux), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, BuildID[sha1]=988cc673af4fba5dcb482f4b34957b99050a68c5, for GNU/Linux 3.2.0, with debug_info, not stripped
gcc/rust1:   ELF 64-bit LSB pie executable, x86-64, version 1 (GNU/Linux), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, BuildID[sha1]=b6a5d3d514446c4dcdee0707f086ab9b274a8a3c, for GNU/Linux 3.2.0, with debug_info, not stripped
gcc/gnat1:   ELF 64-bit LSB pie executable, x86-64, version 1 (GNU/Linux), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, BuildID[sha1]=bb11ccdc2c366fe3fe0980476bcd8ca19b67f9dc, for GNU/Linux 3.2.0, with debug_info, not stripped

I plan to add an option to link with -Wl,-z,now.

Bootstrapped on x86_64-pc-linux-gnu with --with-included-gettext
--enable-host-pie as well as without --enable-host-pie.  Also tested
on a Debian system where the system gcc was configured with
--enable-default-pie.

Co-Authored by: Iain Sandoe  <iain@sandoe.co.uk>

ChangeLog:

	* configure.ac (--enable-host-pie): New check.  Set PICFLAG after this
	check.
	* configure: Regenerate.

c++tools/ChangeLog:

	* Makefile.in: Rename PIEFLAG to PICFLAG.  Set LD_PICFLAG.  Use it.
	Use pic/libiberty.a if PICFLAG is set.
	* configure.ac (--enable-default-pie): Set PICFLAG instead of PIEFLAG.
	(--enable-host-pie): New check.
	* configure: Regenerate.

fixincludes/ChangeLog:

	* Makefile.in: Set and use PICFLAG and LD_PICFLAG.  Use the "pic"
	build of libiberty if PICFLAG is set.
	* configure.ac:
	* configure: Regenerate.

gcc/ChangeLog:

	* Makefile.in: Set LD_PICFLAG.  Use it.  Set enable_host_pie.
	Remove NO_PIE_CFLAGS and NO_PIE_FLAG.  Pass LD_PICFLAG to
	ALL_LINKERFLAGS.  Use the "pic" build of libiberty if --enable-host-pie.
	* configure.ac (--enable-host-shared): Don't set PICFLAG here.
	(--enable-host-pie): New check.  Set PICFLAG and LD_PICFLAG after this
	check.
	* configure: Regenerate.
	* doc/install.texi: Document --enable-host-pie.

gcc/ada/ChangeLog:

	* gcc-interface/Make-lang.in (ALL_ADAFLAGS): Remove NO_PIE_CFLAGS.  Add
	PICFLAG.  Use PICFLAG when building ada/b_gnat1.o and ada/b_gnatb.o.
	* gcc-interface/Makefile.in: Use pic/libiberty.a if PICFLAG is set.
	Remove NO_PIE_FLAG.

gcc/m2/ChangeLog:

	* Make-lang.in: New var, GM2_PICFLAGS.  Use it.

gcc/d/ChangeLog:

	* Make-lang.in: Remove NO_PIE_CFLAGS.

intl/ChangeLog:

	* Makefile.in: Use @PICFLAG@ in COMPILE as well.
	* configure.ac (--enable-host-shared): Don't set PICFLAG here.
	(--enable-host-pie): New check.  Set PICFLAG after this check.
	* configure: Regenerate.

libcody/ChangeLog:

	* Makefile.in: Pass LD_PICFLAG to LDFLAGS.
	* configure.ac (--enable-host-shared): Don't set PICFLAG here.
	(--enable-host-pie): New check.  Set PICFLAG and LD_PICFLAG after this
	check.
	* configure: Regenerate.

libcpp/ChangeLog:

	* configure.ac (--enable-host-shared): Don't set PICFLAG here.
	(--enable-host-pie): New check.  Set PICFLAG after this check.
	* configure: Regenerate.

libdecnumber/ChangeLog:

	* configure.ac (--enable-host-shared): Don't set PICFLAG here.
	(--enable-host-pie): New check.  Set PICFLAG after this check.
	* configure: Regenerate.

libiberty/ChangeLog:

	* configure.ac: Also set shared when enable_host_pie.
	* configure: Regenerate.

zlib/ChangeLog:

	* configure.ac (--enable-host-shared): Don't set PICFLAG here.
	(--enable-host-pie): New check.  Set PICFLAG after this check.
	* configure: Regenerate.

Instantiations of templated conversion operators failed to demangle
for cases such as 'operator X<int>', but worked for 'operator X<int>
&', due to thinking the template instantiation of X was the
instantiation of the conversion operator itself.

	libiberty/
	* cp-demangle.c (d_print_conversion): Remove incorrect
	template instantiation handling.
	* testsuite/demangle-expected: Add testcases.

You are right, this is also a remnant of the old function design
that I completely missed.    Here is the follow-up patch for that.

Thanks for pointing it out.

Costas

On Tue, 6 Jun 2023 at 04:12, Jeff Law <jeffreyalaw@gmail.com> wrote:

    On 6/5/23 08:37, Costas Argyris via Gcc-patches wrote:
    > writeargv can be simplified by getting rid of the error exit mode
    > that was only relevant many years ago when the function used
    > to open the file descriptor internally.
    [ ... ]
    Thanks.  I've pushed this to the trunk.

    You could (as a follow-up) simplify it even further.  There's no need
    for the status variable as far as I can tell.  You could just have the
    final return be "return 0;" instead of "return status;".

libiberty/
	* argv.c (writeargv): Constant propagate "0" for "status",
	simplifying the code slightly.

writeargv can be simplified by getting rid of the error exit mode
that was only relevant many years ago when the function used
to open the file descriptor internally.

0001-libiberty-writeargv-Simplify-function-error-mode.patch

From 1271552baee5561fa61652f4ca7673c9667e4f8f Mon Sep 17 00:00:00 2001
From: Costas Argyris <costas.argyris@gmail.com>
Date: Mon, 5 Jun 2023 15:02:06 +0100
Subject: [PATCH] libiberty: writeargv: Simplify function error mode.

The goto-based error mode was based on a previous version
of the function where it was responsible for opening the
file, so it had to close it upon any exit:

https://inbox.sourceware.org/gcc-patches/20070417200340.GM9017@sparrowhawk.codesourcery.com/



(thanks pinskia)

This is no longer the case though since now the function
takes the file descriptor as input, so the exit mode on
error can be just a simple return 1 statement.

libiberty/
	* argv.c (writeargv): Simplify & remove gotos.

Signed-off-by: Costas Argyris <costas.argyris@gmail.com>

libiberty/ChangeLog:

	* pex-win32.c: fix typos.

Signed-off-by: Costas Argyris <costas.argyris@gmail.com>
Signed-off-by: Jonathan Yong <10walls@gmail.com>

pex-win32.c (win32_spawn): If the command line for CreateProcess
exceeds the 32k Windows limit, try to store it in a temporary
response file and call CreateProcess with @file instead (PR71850).

Signed-off-by: Costas Argyris <costas.argyris@gmail.com>
Signed-off-by: Jonathan Yong <10walls@gmail.com>

libiberty/ChangeLog:

	* pex-win32.c (win32_spawn): Check command line length
	and generate a response file if necessary.
	(spawn_script): Adjust parameters.
	(pex_win32_exec_child): Ditto.

Signed-off-by: Jonathan Yong <10walls@gmail.com>

This implements noexcept(expr) mangling and demangling as per the
Itanium ABI.

	PR c++/70790

gcc/cp/ChangeLog:

	* mangle.cc (write_expression): Handle NOEXCEPT_EXPR.

libiberty/ChangeLog:

	* cp-demangle.c (cplus_demangle_operators): Add the noexcept
	operator.
	(d_print_comp_inner) <case DEMANGLE_COMPONENT_UNARY>: Always
	print parens around the operand of noexcept too.
	* testsuite/demangle-expected: Test noexcept operator
	demangling.

gcc/testsuite/ChangeLog:

	* g++.dg/abi/mangle78.C: New test.

On Fri, Nov 13, 2020 at 11:53:43AM -0700, Jeff Law via Gcc-patches wrote:
>
> On 5/1/20 6:06 PM, Seija Kijin via Gcc-patches wrote:
> > The original code in libiberty says "FIXME" and then says it has not been
> > validated to be ANSI compliant. However, this patch changes the function to
> > match implementations that ARE compliant, and such code is in the public
> > domain.
> >
> > I ran the test results, and there are no test failures.
>
> Thanks.  This seems to be the standard "simple" strstr implementation. 
> There's significantly faster implementations available, but I doubt it's
> worth the effort as the version in this file only gets used if there is
> no system strstr.c.

Except that PR109306 says the new version is non-compliant and
is certainly slower than what we used to have.  The only problem I see
on the old version (sure, it is not very fast version) is that for
strstr ("abcd", "") it returned "abcd"+4 rather than "abcd" because
strchr in that case changed p to point to the last character and then
strncmp returned 0.

The question reported in PR109306 is whether memcmp is required not to
access characters beyond the first difference or not.
For all of memcmp/strcmp/strncmp, C17 says:
"The sign of a nonzero value returned by the comparison functions memcmp, strcmp, and strncmp
is determined by the sign of the difference between the values of the first pair of characters (both
interpreted as unsigned char) that differ in the objects being compared."
but then in memcmp description says:
"The memcmp function compares the first n characters of the object pointed to by s1 to the first n
characters of the object pointed to by s2."
rather than something similar to strncmp wording:
"The strncmp function compares not more than n characters (characters that follow a null character
are not compared) from the array pointed to by s1 to the array pointed to by
s2."
So, while for strncmp it seems clearly well defined when there is zero
terminator before reaching the n, for memcmp it is unclear if say
int
memcmp (const void *s1, const void *s2, size_t n)
{
  int ret = 0;
  size_t i;
  const unsigned char *p1 = (const unsigned char *) s1;
  const unsigned char *p2 = (const unsigned char *) s2;

  for (i = n; i; i--)
    if (p1[i - 1] != p2[i - 1])
      ret = p1[i - 1] < p2[i - 1] ? -1 : 1;
  return ret;
}
wouldn't be valid implementation (one which always compares all characters
and just returns non-zero from the first one that differs).

So, shouldn't we just revert and handle the len == 0 case correctly?

I think almost nothing really uses it, but still, the old version
at least worked nicer with a fast strchr.
Could as well strncmp (p + 1, s2 + 1, len - 1) if that is preferred
because strchr already compared the first character.

2023-04-02  Jakub Jelinek  <jakub@redhat.com>

	PR other/109306
	* strstr.c: Revert the 2020-11-13 changes.
	(strstr): Return s1 if len is 0.

longjmp is not specific to Glibc, and GCC supports lots of systems
that do not use Glibc. Plus this link has been broken in the web
version for ages without a good way to fix.

libiberty/ChangeLog:

	* obstacks.texi (Preparing for Obstacks): Remove a (broken)
	reference to the Glibc manual.

Fix memory leak of cmdline buffer and refactor to have
cleanup code appear once for all exit cases.

libiberty/ChangeLog:

	* pex-win32.c (win32_spawn): Fix memory leak of cmdline
	buffer and refactor to have cleanup code appear once
	for all exit cases.

Signed-off-by: Jonathan Yong <10walls@gmail.com>

gcc computes the wrong prefix if invoked through an NTFS
symlink. Try to resolve it if possible.

PR/108350

libiberty/ChangeLog:

	* lrealpath.c (lrealpath): try to resolve symlink and
	use UNC paths where applicable.

Signed-off-by: Jonathan Yong <10walls@gmail.com>

Recently, mingw-w64 has got updated <msxml.h> from Wine which is included
indirectly by <windows.h> if `WIN32_LEAN_AND_MEAN` is not defined. The
`IXMLDOMDocument` class has a member function named `abort()`, which gets
affected by our `abort()` macro in "system.h".

`WIN32_LEAN_AND_MEAN` should, nevertheless, always be defined. This
can exclude 'APIs such as Cryptography, DDE, RPC, Shell, and Windows
Sockets' [1], and speed up compilation of these files a bit.

[1] https://learn.microsoft.com/en-us/windows/win32/winprog/using-the-windows-headers

gcc/

	PR middle-end/108300
	* config/xtensa/xtensa-dynconfig.c: Define `WIN32_LEAN_AND_MEAN`
	before <windows.h>.
	* diagnostic-color.cc: Likewise.
	* plugin.cc: Likewise.
	* prefix.cc: Likewise.

gcc/ada/

	PR middle-end/108300
	* adaint.c: Define `WIN32_LEAN_AND_MEAN` before `#include
	<windows.h>`.
	* cio.c: Likewise.
	* ctrl_c.c: Likewise.
	* expect.c: Likewise.
	* gsocket.h: Likewise.
	* mingw32.h: Likewise.
	* mkdir.c: Likewise.
	* rtfinal.c: Likewise.
	* rtinit.c: Likewise.
	* seh_init.c: Likewise.
	* sysdep.c: Likewise.
	* terminals.c: Likewise.
	* tracebak.c: Likewise.

gcc/jit/

	PR middle-end/108300
	* jit-w32.h: Define `WIN32_LEAN_AND_MEAN` before <windows.h>.

libatomic/

	PR middle-end/108300
	* config/mingw/lock.c: Define `WIN32_LEAN_AND_MEAN` before
	<windows.h>.

libffi/

	PR middle-end/108300
	* src/aarch64/ffi.c: Define `WIN32_LEAN_AND_MEAN` before
	<windows.h>.

libgcc/

	PR middle-end/108300
	* config/i386/enable-execute-stack-mingw32.c: Define
	`WIN32_LEAN_AND_MEAN` before <windows.h>.
	* libgcc2.c: Likewise.
	* unwind-generic.h: Likewise.

libgfortran/

	PR middle-end/108300
	* intrinsics/sleep.c: Define `WIN32_LEAN_AND_MEAN` before
	<windows.h>.

libgomp/

	PR middle-end/108300
	* config/mingw32/proc.c: Define `WIN32_LEAN_AND_MEAN` before
	<windows.h>.

libiberty/

	PR middle-end/108300
	* make-temp-file.c: Define `WIN32_LEAN_AND_MEAN` before <windows.h>.
	* pex-win32.c: Likewise.

libssp/

	PR middle-end/108300
	* ssp.c: Define `WIN32_LEAN_AND_MEAN` before <windows.h>.

libstdc++-v3/

	PR middle-end/108300
	* src/c++11/system_error.cc: Define `WIN32_LEAN_AND_MEAN` before
	<windows.h>.
	* src/c++11/thread.cc: Likewise.
	* src/c++17/fs_ops.cc: Likewise.
	* src/filesystem/ops.cc: Likewise.

libvtv/

	PR middle-end/108300
	* vtv_malloc.cc: Define `WIN32_LEAN_AND_MEAN` before <windows.h>.
	* vtv_rts.cc: Likewise.
	* vtv_utils.cc: Likewise.

This reverts commit 251c72a6.

This patch implements the --enable-host-pie configure option which
makes the compiler executables PIE.  This can be used to enhance
protection against ROP attacks, and can be viewed as part of a wider
trend to harden binaries.

It is similar to the option --enable-host-shared, except that --e-h-s
won't add -shared to the linker flags whereas --e-h-p will add -pie.
It is different from --enable-default-pie because that option just
adds an implicit -fPIE/-pie when the compiler is invoked, but the
compiler itself isn't PIE.

Since r12-5768-gfe7c3ecf, PCH works well with PIE, so there are no PCH
regressions.

When building the compiler, the build process may use various in-tree
libraries; these need to be built with -fPIE so that it's possible to
use them when building a PIE.  For instance, when --with-included-gettext
is in effect, intl object files must be compiled with -fPIE.  Similarly,
when building in-tree gmp, isl, mpfr and mpc, they must be compiled with
-fPIE.

I plan to add an option to link with -Wl,-z,now.

ChangeLog:

	* Makefile.def: Pass $(PICFLAG) to AM_CFLAGS for gmp, mpfr, mpc, and
	isl.
	* Makefile.in: Regenerate.
	* Makefile.tpl: Set PICFLAG.
	* configure.ac (--enable-host-pie): New check.  Set PICFLAG after this
	check.
	* configure: Regenerate.

c++tools/ChangeLog:

	* Makefile.in: Rename PIEFLAG to PICFLAG.  Set LD_PICFLAG.  Use it.
	Use pic/libiberty.a if PICFLAG is set.
	* configure.ac (--enable-default-pie): Set PICFLAG instead of PIEFLAG.
	(--enable-host-pie): New check.
	* configure: Regenerate.

fixincludes/ChangeLog:

	* Makefile.in: Set and use PICFLAG and LD_PICFLAG.  Use the "pic"
	build of libiberty if PICFLAG is set.
	* configure.ac:
	* configure: Regenerate.

gcc/ChangeLog:

	* Makefile.in: Set LD_PICFLAG.  Use it.  Set enable_host_pie.
	Remove NO_PIE_CFLAGS and NO_PIE_FLAG.  Pass LD_PICFLAG to
	ALL_LINKERFLAGS.  Use the "pic" build of libiberty if --enable-host-pie.
	* configure.ac (--enable-host-shared): Don't set PICFLAG here.
	(--enable-host-pie): New check.  Set PICFLAG and LD_PICFLAG after this
	check.
	* configure: Regenerate.
	* doc/install.texi: Document --enable-host-pie.

gcc/d/ChangeLog:

	* Make-lang.in: Remove NO_PIE_CFLAGS.

intl/ChangeLog:

	* Makefile.in: Use @PICFLAG@ in COMPILE as well.
	* configure.ac (--enable-host-shared): Don't set PICFLAG here.
	(--enable-host-pie): New check.  Set PICFLAG after this check.
	* configure: Regenerate.

libcody/ChangeLog:

	* Makefile.in: Pass LD_PICFLAG to LDFLAGS.
	* configure.ac (--enable-host-shared): Don't set PICFLAG here.
	(--enable-host-pie): New check.  Set PICFLAG and LD_PICFLAG after this
	check.
	* configure: Regenerate.

libcpp/ChangeLog:

	* configure.ac (--enable-host-shared): Don't set PICFLAG here.
	(--enable-host-pie): New check.  Set PICFLAG after this check.
	* configure: Regenerate.

libdecnumber/ChangeLog:

	* configure.ac (--enable-host-shared): Don't set PICFLAG here.
	(--enable-host-pie): New check.  Set PICFLAG after this check.
	* configure: Regenerate.

libiberty/ChangeLog:

	* configure.ac: Also set shared when enable_host_pie.
	* configure: Regenerate.

zlib/ChangeLog:

	* configure.ac (--enable-host-shared): Don't set PICFLAG here.
	(--enable-host-pie): New check.  Set PICFLAG after this check.
	* configure: Regenerate.

Templated lambdas have a template-head, which is part of their
signature.  GCC ABI 18 mangles that into the lambda name.  This adds
support to the demangler.  We have to introduce artificial template
parameter names, as we need to refer to them from later components of
the lambda signature. We use $T:n, $N:n and $TT:n for type, non-type
and template parameters.  Non-type parameter names are not shown in
the strictly correct location -- for instance 'int (&NT) ()' would be
shown as 'int (&) $N:n'.  That's unfortunate, but an orthogonal issue.
The 'is_lambda_arg' field is now repurposed as indicating the number
of explicit template parameters (1-based).

	include/
	* demangle.h (enum demangle_component_type): Add
	DEMANGLE_COMPONENT_TEMPLATE_HEAD,
	DEMANGLE_COMPONENT_TEMPLATE_TYPE_PARM,
	DEMANGLE_COMPONENT_TEMPLATE_NON_TYPE_PARM,
	DEMANGLE_COMPONENT_TEMPLATE_TEMPLATE_PARM,
	DEMANGLE_COMPONENT_TEMPLATE_PACK_PARM.
	libiberty/
	* cp-demangle.c (struct d_print_info): Rename is_lambda_arg to
	lambda_tpl_parms.  Augment semantics.
	(d_make_comp): Add checks for new components.
	(d_template_parm, d_template_head): New.
	(d_lambda): Add templated lambda support.
	(d_print_init): Adjust.
	(d_print_lambda_parm_name): New.
	(d_print_comp_inner): Support templated lambdas,
	* testsuite/demangle-expected: Add testcases.

This reverts commit c63539ff.

This reverts commit 41a45cba.

This reverts commit 54ca4eef.

This reverts commit 1f5a932e.

This reverts commit 3ed1b4ce.

This reverts commit bd044dae.

This reverts commit 5e749ee3.

During the Sphinx-migration development, I used
SPHINX_BUILD='' in order to skip building info and manual
pages in gcc folder. However, we've got HAS_SPHINX_BUILD
which is the correct flag for that.

With the patch, one will get a nicer error message when
sphinx-build is missing and one builds (explicitly) a target which
depends on it.

	PR other/107620

gcc/ChangeLog:

	* configure: Regenerate.
	* configure.ac: Always set sphinx-build.

libgomp/ChangeLog:

	* configure: Regenerate.
	* configure.ac: Always set sphinx-build.

libiberty/ChangeLog:

	* configure: Regenerate.
	* configure.ac: Always set sphinx-build.

libitm/ChangeLog:

	* configure: Regenerate.
	* configure.ac: Always set sphinx-build.

libquadmath/ChangeLog:

	* configure: Regenerate.
	* configure.ac: Always set sphinx-build.