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# serial 9 -*- Autoconf -*-
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# Enable extensions on systems that normally disable them.
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# Copyright (C) 2003, 2006-2010 Free Software Foundation, Inc.
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# This file is free software; the Free Software Foundation
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# gives unlimited permission to copy and/or distribute it,
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# with or without modifications, as long as this notice is preserved.
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# This definition of AC_USE_SYSTEM_EXTENSIONS is stolen from CVS
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# Autoconf. Perhaps we can remove this once we can assume Autoconf
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# 2.62 or later everywhere, but since CVS Autoconf mutates rapidly
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# enough in this area it's likely we'll need to redefine
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# AC_USE_SYSTEM_EXTENSIONS for quite some time.
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# If autoconf reports a warning
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# warning: AC_COMPILE_IFELSE was called before AC_USE_SYSTEM_EXTENSIONS
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# or warning: AC_RUN_IFELSE was called before AC_USE_SYSTEM_EXTENSIONS
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# 1) to ensure that AC_USE_SYSTEM_EXTENSIONS is never directly invoked
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# but always AC_REQUIREd,
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# 2) to ensure that for each occurrence of
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# AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS])
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# AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
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# the corresponding gnulib module description has 'extensions' among
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# its dependencies. This will ensure that the gl_USE_SYSTEM_EXTENSIONS
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# invocation occurs in gl_EARLY, not in gl_INIT.
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# AC_USE_SYSTEM_EXTENSIONS
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# ------------------------
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# Enable extensions on systems that normally disable them,
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# typically due to standards-conformance issues.
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# Remember that #undef in AH_VERBATIM gets replaced with #define by
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# AC_DEFINE. The goal here is to define all known feature-enabling
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# macros, then, if reports of conflicts are made, disable macros that
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# cause problems on some platforms (such as __EXTENSIONS__).
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AC_DEFUN_ONCE([AC_USE_SYSTEM_EXTENSIONS],
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[AC_BEFORE([$0], [AC_COMPILE_IFELSE])dnl
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AC_BEFORE([$0], [AC_RUN_IFELSE])dnl
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AC_REQUIRE([AC_CANONICAL_HOST])
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AC_CHECK_HEADER([minix/config.h], [MINIX=yes], [MINIX=])
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if test "$MINIX" = yes; then
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AC_DEFINE([_POSIX_SOURCE], [1],
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[Define to 1 if you need to in order for `stat' and other
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AC_DEFINE([_POSIX_1_SOURCE], [2],
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[Define to 2 if the system does not provide POSIX.1 features
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except with this defined.])
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AC_DEFINE([_MINIX], [1],
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[Define to 1 if on MINIX.])
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dnl HP-UX 11.11 defines mbstate_t only if _XOPEN_SOURCE is defined to 500,
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dnl regardless of whether the flags -Ae or _D_HPUX_SOURCE=1 are already
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AC_DEFINE([_XOPEN_SOURCE], [500],
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[Define to 500 only on HP-UX.])
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AH_VERBATIM([__EXTENSIONS__],
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[/* Enable extensions on AIX 3, Interix. */
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/* Enable GNU extensions on systems that have them. */
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/* Enable threading extensions on Solaris. */
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#ifndef _POSIX_PTHREAD_SEMANTICS
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# undef _POSIX_PTHREAD_SEMANTICS
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/* Enable extensions on HP NonStop. */
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#ifndef _TANDEM_SOURCE
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# undef _TANDEM_SOURCE
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/* Enable general extensions on Solaris. */
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#ifndef __EXTENSIONS__
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# undef __EXTENSIONS__
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AC_CACHE_CHECK([whether it is safe to define __EXTENSIONS__],
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[ac_cv_safe_to_define___extensions__],
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# define __EXTENSIONS__ 1
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]AC_INCLUDES_DEFAULT])],
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[ac_cv_safe_to_define___extensions__=yes],
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[ac_cv_safe_to_define___extensions__=no])])
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test $ac_cv_safe_to_define___extensions__ = yes &&
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AC_DEFINE([__EXTENSIONS__])
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AC_DEFINE([_ALL_SOURCE])
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AC_DEFINE([_GNU_SOURCE])
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AC_DEFINE([_POSIX_PTHREAD_SEMANTICS])
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AC_DEFINE([_TANDEM_SOURCE])
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])# AC_USE_SYSTEM_EXTENSIONS
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# gl_USE_SYSTEM_EXTENSIONS
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# ------------------------
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# Enable extensions on systems that normally disable them,
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# typically due to standards-conformance issues.
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AC_DEFUN_ONCE([gl_USE_SYSTEM_EXTENSIONS],
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dnl Require this macro before AC_USE_SYSTEM_EXTENSIONS.
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dnl gnulib does not need it. But if it gets required by third-party macros
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dnl after AC_USE_SYSTEM_EXTENSIONS is required, autoconf 2.62..2.63 emit a
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dnl warning: "AC_COMPILE_IFELSE was called before AC_USE_SYSTEM_EXTENSIONS".
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dnl Note: We can do this only for one of the macros AC_AIX, AC_GNU_SOURCE,
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dnl AC_MINIX. If people still use AC_AIX or AC_MINIX, they are out of luck.
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AC_REQUIRE([AC_GNU_SOURCE])
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AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS])