Bruno Haible [Sat, 5 Feb 2011 13:23:31 +0000 (14:23 +0100)]
New module 'wcscpy'.
* modules/wcscpy: New file.
* lib/wchar.in.h (wcscpy): New declaration.
* lib/wcscpy.c: New file.
* lib/wcscpy-impl.h: New file, from libutf8 with modifications.
* m4/wcscpy.m4: New file.
* m4/wchar_h.m4 (gl_WCHAR_H): Test whether wcscpy is declared.
(gl_WCHAR_H_DEFAULTS): Initialize GNULIB_WCSCPY, HAVE_WCSCPY.
* modules/wchar (Makefile.am): Substitute GNULIB_WCSCPY, HAVE_WCSCPY.
* tests/test-wchar-c++.cc: Test the declaration of wcscpy.
* doc/posix-functions/wcscpy.texi: Mention the new module.
Bruno Haible [Sat, 5 Feb 2011 12:45:22 +0000 (13:45 +0100)]
New module 'wcsnlen'.
* modules/wcsnlen: New file.
* lib/wchar.in.h (wcsnlen): New declaration.
* lib/wcsnlen.c: New file.
* lib/wcsnlen-impl.h: New file, from libutf8 with modifications.
* m4/wcsnlen.m4: New file.
* m4/wchar_h.m4 (gl_WCHAR_H): Test whether wcsnlen is declared.
(gl_WCHAR_H_DEFAULTS): Initialize GNULIB_WCSNLEN, HAVE_WCSNLEN.
* modules/wchar (Makefile.am): Substitute GNULIB_WCSNLEN, HAVE_WCSNLEN.
* tests/test-wchar-c++.cc: Test the declaration of wcsnlen.
* doc/posix-functions/wcsnlen.texi: Mention the new module.
Bruno Haible [Sat, 5 Feb 2011 12:36:58 +0000 (13:36 +0100)]
New module 'wcslen'.
* modules/wcslen: New file.
* lib/wchar.in.h (wcslen): New declaration.
* lib/wcslen.c: New file.
* lib/wcslen-impl.h: New file, from libutf8 with modifications.
* m4/wcslen.m4: New file.
* m4/wchar_h.m4 (gl_WCHAR_H): Test whether wcslen is declared.
(gl_WCHAR_H_DEFAULTS): Initialize GNULIB_WCSLEN, HAVE_WCSLEN.
* modules/wchar (Makefile.am): Substitute GNULIB_WCSLEN, HAVE_WCSLEN.
* tests/test-wchar-c++.cc: Test the declaration of wcslen.
* doc/posix-functions/wcslen.texi: Mention the new module.
Bruno Haible [Sat, 5 Feb 2011 12:28:21 +0000 (13:28 +0100)]
New module 'wmemset'.
* modules/wmemset: New file.
* lib/wchar.in.h (wmemset): New declaration.
* lib/wmemset.c: New file.
* lib/wmemset-impl.h: New file, from libutf8 with modifications.
* m4/wmemset.m4: New file.
* m4/wchar_h.m4 (gl_WCHAR_H): Test whether wmemset is declared.
(gl_WCHAR_H_DEFAULTS): Initialize GNULIB_WMEMSET, HAVE_WMEMSET.
* modules/wchar (Makefile.am): Substitute GNULIB_WMEMSET, HAVE_WMEMSET.
* tests/test-wchar-c++.cc: Test the declaration of wmemset.
* doc/posix-functions/wmemset.texi: Mention the new module.
Bruno Haible [Sat, 5 Feb 2011 12:07:51 +0000 (13:07 +0100)]
New module 'wmemmove'.
* modules/wmemmove: New file.
* lib/wchar.in.h (wmemmove): New declaration.
* lib/wmemmove.c: New file.
* lib/wmemmove-impl.h: New file, from libutf8 with modifications.
* m4/wmemmove.m4: New file.
* m4/wchar_h.m4 (gl_WCHAR_H): Test whether wmemmove is declared.
(gl_WCHAR_H_DEFAULTS): Initialize GNULIB_WMEMMOVE, HAVE_WMEMMOVE.
* modules/wchar (Makefile.am): Substitute GNULIB_WMEMMOVE,
HAVE_WMEMMOVE.
* tests/test-wchar-c++.cc: Test the declaration of wmemmove.
* doc/posix-functions/wmemmove.texi: Mention the new module.
Bruno Haible [Sat, 5 Feb 2011 11:58:40 +0000 (12:58 +0100)]
New module 'wmemcpy'.
* modules/wmemcpy: New file.
* lib/wchar.in.h (wmemcpy): New declaration.
* lib/wmemcpy.c: New file.
* lib/wmemcpy-impl.h: New file, from libutf8 with modifications.
* m4/wmemcpy.m4: New file.
* m4/wchar_h.m4 (gl_WCHAR_H): Test whether wmemcpy is declared.
(gl_WCHAR_H_DEFAULTS): Initialize GNULIB_WMEMCPY, HAVE_WMEMCPY.
* modules/wchar (Makefile.am): Substitute GNULIB_WMEMCPY, HAVE_WMEMCPY.
* tests/test-wchar-c++.cc: Test the declaration of wmemcpy.
* doc/posix-functions/wmemcpy.texi: Mention the new module.
Bruno Haible [Sat, 5 Feb 2011 11:47:22 +0000 (12:47 +0100)]
New module 'wmemcmp'.
* modules/wmemcmp: New file.
* lib/wchar.in.h (wmemcmp): New declaration.
* lib/wmemcmp.c: New file.
* lib/wmemcmp-impl.h: New file, from libutf8 with modifications.
* m4/wmemcmp.m4: New file.
* m4/wchar_h.m4 (gl_WCHAR_H): Test whether wmemcmp is declared.
(gl_WCHAR_H_DEFAULTS): Initialize GNULIB_WMEMCMP, HAVE_WMEMCMP.
* modules/wchar (Makefile.am): Substitute GNULIB_WMEMCMP, HAVE_WMEMCMP.
* tests/test-wchar-c++.cc: Test the declaration of wmemcmp.
* doc/posix-functions/wmemcmp.texi: Mention the new module.
Bruce Korb [Sun, 6 Feb 2011 20:11:40 +0000 (21:11 +0100)]
libposix: Revert the unreviewed part of yesterday's big merge.
Back out yesterday's big merge from the libposix branch, except for the
openat-die.c change that was reviewed and approved by Paul Eggert.
Put the ChangeLog entry at the top, to reflect the order of changes in the
master branch.
Eric Blake [Sat, 5 Feb 2011 21:31:59 +0000 (14:31 -0700)]
unsetenv: work around Haiku issues
On Haiku alpha 2, test-unsetenv.c passed in isolation with just
system headers, but failed when libgnu and replacement headers
were in use. Why? Because putenv("a") fails to remove "a=..."
from the environment, but the gnulib rpl_putenv works by
assigning to environ. Apparently, Haiku is doing some funky
caching issues, and correctly removes all vestiges of environment
duplicates when Haiku is in charge, but not after assigning to
environ forces Haiku to rebuild its cache.
The m4 change is sufficient to detect Haiku's oddities, and the
existing replacement then passes just fine.
* m4/setenv.m4 (gl_FUNC_UNSETENV): Also detect Haiku issue.
* doc/posix-functions/unsetenv.texi (unsetenv): Document it.
Bruce Korb [Sat, 5 Feb 2011 16:22:48 +0000 (08:22 -0800)]
libposix: Add _HEADERS primaries to posix modules.
Modify gnulib-tool to strip them from generated Makefile.am-s where
they are not needed. Also, replace M4 macro prefixes when requested.
Finally, omit calls to error() for libposix.
Bruno Haible [Sat, 5 Feb 2011 11:25:13 +0000 (12:25 +0100)]
New module 'wmemchr'.
* modules/wmemchr: New file.
* lib/wchar.in.h (wmemchr): New declaration.
* lib/wmemchr.c: New file.
* lib/wmemchr-impl.h: New file, from libutf8 with modifications.
* m4/wmemchr.m4: New file.
* m4/wchar_h.m4 (gl_WCHAR_H_DEFAULTS): Initialize GNULIB_WMEMCHR,
HAVE_WMEMCHR.
* modules/wchar (Makefile.am): Substitute GNULIB_WMEMCHR, HAVE_WMEMCHR.
* tests/test-wchar-c++.cc: Test the declaration of wmemchr.
* doc/posix-functions/wmemchr.texi: Mention the new module.
Eric Blake [Sat, 5 Feb 2011 04:52:40 +0000 (21:52 -0700)]
fdopendir: detect FreeBSD bug
FreeBSD fdopendir(fd) always consumes fd, even if it fails with
ENOTDIR. The code that works around the GNU Hurd bug also fixes this;
we just need to detect it.
* m4/fdopendir.m4 (gl_FUNC_FDOPENDIR): Detect bug.
* doc/posix-functions/fdopendir.texi (fdopendir): Document it.
Reported by Jim Meyering.
Paul Eggert [Sat, 5 Feb 2011 04:54:58 +0000 (20:54 -0800)]
stdbool: do not define HAVE_STDBOOL_H
* m4/stdbool.m4 (AC_CHECK_HEADER_STDBOOL): Renamed from
AC_HEADER_STDBOOL. All uses changed. Do not define
HAVE_STDBOOL_H, as gnulib does not need this. This change is
imported from the latest Autoconf git. It was motivated by Emacs,
which uses gnulib but does not need HAVE_STDBOOL_H.
Bruno Haible [Sat, 5 Feb 2011 01:25:14 +0000 (02:25 +0100)]
wcsnrtombs: Prepare for new module wwcsnrtombs.
* lib/wcsnrtombs-impl.h: New file, extracted from lib/wcsnrtombs.c.
* lib/wcsnrtombs.c: Include it.
* modules/wcsnrtombs (Files): Add lib/wcsnrtombs-impl.h.
Bruno Haible [Sat, 5 Feb 2011 01:24:20 +0000 (02:24 +0100)]
wcsrtombs: Prepare for new module wwcsrtombs.
* lib/wcsrtombs-impl.h: New file, extracted from lib/wcsrtombs.c.
* lib/wcsrtombs.c: Include it.
* modules/wcsrtombs (Files): Add lib/wcsrtombs-impl.h.
Bruno Haible [Sat, 5 Feb 2011 01:22:38 +0000 (02:22 +0100)]
mbsnrtowcs: Prepare for new module mbsnrtowwcs.
* lib/mbsnrtowcs-impl.h: New file, extracted from lib/mbsnrtowcs.c.
* lib/mbsnrtowcs.c: Include it.
* modules/mbsnrtowcs (Files): Add lib/mbsnrtowcs-impl.h.
Bruno Haible [Sat, 5 Feb 2011 01:21:03 +0000 (02:21 +0100)]
mbsrtowcs: Prepare for new module mbsrtowwcs.
* lib/mbsrtowcs-impl.h: New file, extracted from lib/mbsrtowcs.c.
* lib/mbsrtowcs.c: Include it.
* modules/mbsrtowcs (Files): Add lib/mbsrtowcs-impl.h.
Bruno Haible [Fri, 4 Feb 2011 18:22:43 +0000 (19:22 +0100)]
vasnprintf: Reduce use of malloc for small format strings.
* lib/printf-args.h (N_DIRECT_ALLOC_ARGUMENTS): New macro.
(arguments): Add room for the first 7 arguments.
* lib/printf-parse.h (N_DIRECT_ALLOC_DIRECTIVES): New macro.
(char_directives, u8_directives, u16_directives, u32_directives): Add
room for the first 7 directives.
* lib/printf-parse.c: Include <string.h>.
(PRINTF_PARSE): Change memory handling code so that it uses the first
7 preallocated elements in an 'arguments' or 'DIRECTIVES' struct.
* lib/vasnprintf.c (VASNPRINTF): Update memory handling code.
Reported by Pádraig Brady <P@draigbrady.com>.
Eric Blake [Tue, 1 Feb 2011 03:14:37 +0000 (20:14 -0700)]
dup2: work around Haiku bug
dup2(n,n) must be a no-op, but on Haiku, it resets FD_CLOEXEC.
However, we must keep the Linux workaround for dup2(n,n)
returning (unsigned int)-EBADF.
* m4/dup2.m4 (gl_FUNC_DUP2): Test for bug.
* lib/dup2.c (rpl_dup2) [!WIN32]: Add workaround.
* doc/posix-functions/dup2.texi (dup2): Document the bug.
* tests/test-dup2.c (main): Enhance test.
Paul Eggert [Sun, 30 Jan 2011 17:36:23 +0000 (09:36 -0800)]
mktime: clarify long_int width checking
* lib/mktime.c (long_int_is_wide_enough): Move this assertion to
the top level, to make it clearer that the assumption about
long_int width is being checked. See
<http://lists.gnu.org/archive/html/bug-gnulib/2011-01/msg00554.html>.
* lib/intprops.h (TYPE_MINIMUM, TYPE_MAXIMUM): Do not shift a
negative number, which the C Standard says has undefined behavior.
In practice this is not a problem, but might as well do it by the book.
Reported by Rich Felker and Eric Blake; see
<http://lists.gnu.org/archive/html/bug-gnulib/2011-01/msg00493.html>.
* lib/strtol.c (TYPE_MINIMUM, TYPE_MAXIMUM): Likewise.
* m4/mktime.m4 (AC_FUNC_MKTIME): Likewise.
* m4/nanosleep.m4 (gl_FUNC_NANOSLEEP): Likewise.
* m4/parse-datetime.m4 (gl_PARSE_DATETIME): Likewise.
* m4/stdint.m4 (gl_STDINT_H): Likewise.
* lib/mktime.c (TYPE_MAXIMUM): Redo slightly to match the others.
* lib/mktime.c (isdst_differ): New function.
(__mktime_internal): Use it systematically for all isdst comparisons.
This completes the fix for libc BZ #6723, and removes the need for
normalizing tm_isdst. See
<http://sourceware.org/bugzilla/show_bug.cgi?id=6723>
(not_equal_tm) [DEBUG]: Use isdst_differ here, too.
Paul Eggert [Sat, 29 Jan 2011 23:47:04 +0000 (15:47 -0800)]
mktime: fix some integer overflow issues and sidestep the rest
This was prompted by a bug report by Benjamin Lindner for MinGW
<http://lists.gnu.org/archive/html/bug-gnulib/2011-01/msg00472.html>.
His bug is due to signed integer overflow (0 - INT_MIN), and I
I scanned through mktime.c looking for other integer overflow
problems, fixing all the bugs I found.
Although the C Standard says the resulting code is still not safe
in the presence of integer overflow, in practice it should be good
enough for all real-world two's-complement implementations, except
for debugging environments that deliberately trap on integer
overflow (e.g., gcc -ftrapv).
* lib/mktime.c (WRAPV): New macro.
(SHR): Also check that long_int and time_t shift right in the
usual way, before using the fast-but-unportable method.
(TYPE_ONES_COMPLEMENT, TYPE_SIGNED_MAGNITUDE): Remove, no longer
used. The code already assumed two's complement, so there's
no need to test for alternatives. All uses removed.
(TYPE_MAXIMUM): Don't rely here on overflow behavior not defined by
the C standard. Problem reported by Rich Felker in
<http://lists.gnu.org/archive/html/bug-gnulib/2011-01/msg00488.html>.
(twos_complement_arithmetic): Also check long_int and time_t.
(time_t_avg, time_t_add_ok, time_t_int_add_ok): New functions.
(guess_time_tm, ranged_convert, __mktime_internal): Use them.
(__mktime_internal): Avoid integer overflow with unary subtraction
in two instances where -1 - X is an adequate replacement for -X,
since the calculations are approximate.
Eric Blake [Thu, 27 Jan 2011 17:06:08 +0000 (10:06 -0700)]
mktime: avoid infinite loop
* m4/mktime.m4 (AC_FUNC_MKTIME): Avoid overflow on possibly-signed
type; behavior is still undefined but portable to all known targets.
Reported by Rich Felker.
Paul Eggert [Sat, 29 Jan 2011 05:02:31 +0000 (21:02 -0800)]
mktime: avoid problems on NetBSD 5 / i386
* lib/mktime.c (long_int): New type. This works around a problem
on NetBSD 5 / i386, where 'long int' and 'int' are both 32 bits
but time_t is 64 bits, and where I expect the existing code is
wrong in some cases.
(leapyear, ydhms_diff, guess_time_tm, __mktime_internal): Use it.
(ydhms_diff): Bring back the compile-time check for wide-enough
year and yday.
Ralf Wildenhues [Sat, 22 Jan 2011 15:44:52 +0000 (16:44 +0100)]
move-if-change: cope with concurrent mv of identical file.
* build-aux/move-if-change (CMPPROG): Accept environment
variable as an override for `cmp'.
(usage): Document CMPPROG.
Adjust comparison to drop stdout. Cope with failure of mv if
the target file exists and is identical to the source, for
parallel builds.
Report from H.J. Lu against binutils in PR binutils/12283.
Bruno Haible [Thu, 27 Jan 2011 10:42:45 +0000 (11:42 +0100)]
vma-iter, get-rusage-as: Add OpenBSD support.
* modules/vma-iter (configure.ac): Test for mquery.
* lib/vma-iter.h (VMA_ITERATE_SUPPORTED): Define also on OpenBSD.
* lib/vma-iter.c: Include <sys/mman.h>.
(vma_iterate): Add an implementation based on mquery().
* lib/resource-ext.h (get_rusage_as): Update comments.
* lib/get-rusage-as.c: Likewise.
* lib/get-rusage-data.c: Likewise.
Eric Blake [Wed, 26 Jan 2011 05:06:16 +0000 (22:06 -0700)]
fcntl: work around Haiku F_DUPFD bugs
* m4/fcntl.m4 (gl_FUNC_FCNTL): Also catch Haiku errno bug.
* lib/fcntl.c (rpl_fcntl) [F_DUPFD]: Work around Haiku losing
cloexec bit on duplication.
* doc/posix-functions/fcntl.texi (fcntl): Document the bug.
Bruno Haible [Mon, 24 Jan 2011 02:56:02 +0000 (03:56 +0100)]
New module 'vma-iter'.
* lib/vma-iter.h: New file.
* lib/vma-iter.c: New file, based on lib/get-rusage-as.c.
* modules/vma-iter: New file.
* lib/get-rusage-as.c: Include vma-iter.h. Don't include system headers
for get_rusage_as_via_iterator.
(vma_iterate_callback): New function.
(get_rusage_as_via_iterator): Rewritten to use vma_iterate.
* modules/get-rusage-as (Depends-on): Add vma-iter.
Paul Eggert [Sat, 22 Jan 2011 06:18:18 +0000 (22:18 -0800)]
getopt: omit HAVE_OPTRESET, HAVE_GETOPT_CLIP from config.h
* m4/getopt.m4 (gl_GETOPT_CHECK_HEADERS): Do not put the
symbols HAVE_OPTRESET and HAVE_GETOPT_CLIP into config.h,
as they are needed only for configure's test case.
This removes two unnecessary symbols from config.h.
Eric Blake [Fri, 21 Jan 2011 16:17:38 +0000 (09:17 -0700)]
bootstrap: minor portability fixes
* build-aux/bootstrap (me): Use $me instead of $0 in functions.
(usage): Omit leading capital and trailing . on help phrases, per
GNU Coding Standards.
(check_versions, top level): Prefix messages with script name.
Bruno Haible [Fri, 21 Jan 2011 13:12:24 +0000 (14:12 +0100)]
uN_strstr: New unit tests.
* modules/unistr/u8-strstr-tests: New file.
* modules/unistr/u16-strstr-tests: New file.
* modules/unistr/u32-strstr-tests: New file.
* tests/unistr/test-u-strstr.h: New file, based on tests/test-strstr.c.
* tests/unistr/test-u8-strstr.c: New file.
* tests/unistr/test-u16-strstr.c: New file.
* tests/unistr/test-u32-strstr.c: New file.
Pádraig Brady [Fri, 21 Jan 2011 08:47:51 +0000 (08:47 +0000)]
test-malloca: unset MALLOC_PERTURB_ to speed up test
* tests/test-malloca.c (main): Unset the environment variable
to greatly speed up the test.
* tests/init.sh: Don't say that MALLOC_PERTURB_ is cheap.
* modules/malloca-tests: Depend on unsetenv.
Jim Meyering [Thu, 20 Jan 2011 07:47:24 +0000 (08:47 +0100)]
init.sh: insert space between each function name and "()"
* tests/init.sh: Make it a little easier to see that a function's
name is "warn_", and not "warn" when looking at the first part of
its definition: "warn_ ()". Suggested by Ralf Wildenhues.
Jim Meyering [Fri, 14 Jan 2011 08:43:00 +0000 (09:43 +0100)]
bootstrap: avoid failure when there is no .gitmodules file
": ${gnulib_path=gnulib}" fails to set $gnulib_path when that variable
has been assigned to, even when its value is the empty string.
* build-aux/bootstrap (gnulib_path): Test explicitly for an empty
"$gnulib_path", rather than using ${gnulib_path=gnulib}.
Reported by John W. Eaton <jwe@gnu.org>.
Jim Meyering [Thu, 20 Jan 2011 08:35:37 +0000 (09:35 +0100)]
mountlist: clean up code formatting
* lib/mountlist.c (read_file_system_list): Split a long line,
correct bracing style, use NULL in place of "(struct statfs *)0",
don't parenthesize return value, add spaces around "=" and after
";-in-for-stmt".
Markus Duft [Thu, 20 Jan 2011 08:19:24 +0000 (09:19 +0100)]
mountlist: add support for Interix
* lib/mountlist.c (read_file_system_list) [MOUNTED_INTERIX_STATVFS]:
Apply statvfs to all entries of /dev/fs.
* m4/ls-mntd-fs.m4 (gl_LIST_MOUNTED_FILE_SYSTEMS): Check for statvfs,
and if found, AC_DEFINE MOUNTED_INTERIX_STATVFS.
Jim Meyering [Thu, 20 Jan 2011 10:50:53 +0000 (11:50 +0100)]
maint.mk: improve the public-submodule-commit rule
* top/maint.mk (public-submodule-commit): Prefix with $(AM_V_GEN),
to suppress printing of its commands... unless V=1.
Add git submodule's --quiet option to suppress printing of e.g.,
"Entering gnulib" output.
"cd" into $(srcdir) before running git submodule.
Bruno Haible [Thu, 20 Jan 2011 10:25:32 +0000 (11:25 +0100)]
include_next: Fix bug introduced on 2011-01-18.
* m4/include_next.m4 (gl_NEXT_HEADERS_INTERNAL): New macro, extracted
from gl_CHECK_NEXT_HEADERS and gl_NEXT_HEADERS. Omit test of
ac_cv_header_... variable if the second argument is not 'check'.
(gl_CHECK_NEXT_HEADERS, gl_NEXT_HEADERS): Invoke
gl_NEXT_HEADERS_INTERNAL.
Jim Meyering [Fri, 14 Jan 2011 08:43:00 +0000 (09:43 +0100)]
bootstrap: avoid failure when there is no .gitmodules file
": ${gnulib_path=gnulib}" fails to set $gnulib_path when that variable
has been assigned to, even when its value is the empty string.
* build-aux/bootstrap (gnulib_path): Test explicitly for an empty
"$gnulib_path", rather than using ${gnulib_path=gnulib}.
Reported by John W. Eaton <jwe@gnu.org>.
Eric Blake [Wed, 19 Jan 2011 17:12:12 +0000 (10:12 -0700)]
c-stack: assume stack overflow if SA_SIGINFO unsupported
* lib/c-stack.c (SIGACTION_WORKS): Rename...
(SIGINFO_WORKS): ...since gnulib module guarantees that (most) of
sigaction will work.
(die): Assume stack overflow if siginfo doesn't work, to let Haiku
behavior match Linux.
* tests/test-c-stack.c (main): Prefer NULL for pointers.
Eric Blake [Wed, 19 Jan 2011 13:17:20 +0000 (06:17 -0700)]
binary-io: fix O_TEXT on Haiku
* modules/binary-io (Depends-on): Add fcntl-h.
* lib/binary-io.h (O_TEXT): Rely on replacement <fcntl.h> rather
than blindly undefining O_TEXT.
Reported by Scott McCreary.
Paul Eggert [Wed, 19 Jan 2011 06:38:10 +0000 (22:38 -0800)]
include_next: do not check for standard headers like stddef.h
I found this problem when modifying Emacs to use gnulib.
I noticed that it added HAVE_STDDEF_H to config.h, even though
gnulib always assumes <stddef.h> exists as per README and this
symbol is unnecessary.
* m4/include_next.m4 (gl_NEXT_HEADERS): New macro, which does not
use AC_CHECK_HEADERS_ONCE, but which otherwise contains what
gl_CHECK_NEXT_HEADERS used to contain. This makes 'configure' run
faster for headers like stddef.h that are known to exist.
(gl_CHECK_NEXT_HEADERS): Use it.
* m4/float_h.m4 (gl_FLOAT_H): For float.h, use gl_NEXT_HEADERS
rather than gl_CHECK_NEXT_HEADERS.
* m4/stdarg.m4 (gl_STDARG_H): Likewise, for stdarg.h.
* m4/stddef_h.m4 (gl_STDDEF_H): Likewise, for stddef.h.