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authorMike Frysinger <vapier@gentoo.org>2012-06-17 20:49:00 -0700
committerMike Frysinger <vapier@gentoo.org>2012-06-23 17:12:36 -0400
commit10d063518923c1452b6ab75a52f71ed2ece4e859 (patch)
tree7f876161f9c40c2bf2c1fe284fadf6dfd79412d4 /m4
parentsandbox: drop beep support (diff)
downloadsandbox-10d063518923c1452b6ab75a52f71ed2ece4e859.tar.gz
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update ax_*.m4 files from upstream
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Diffstat (limited to 'm4')
-rw-r--r--m4/ax_append_flag.m469
-rw-r--r--m4/ax_cflags_warn_all.m4134
-rw-r--r--m4/ax_check_compile_flag.m4 (renamed from m4/ax_check_compiler_flags.m4)64
-rw-r--r--m4/ax_check_link_flag.m4 (renamed from m4/ax_check_linker_flags.m4)62
4 files changed, 157 insertions, 172 deletions
diff --git a/m4/ax_append_flag.m4 b/m4/ax_append_flag.m4
new file mode 100644
index 0000000..1d38b76
--- /dev/null
+++ b/m4/ax_append_flag.m4
@@ -0,0 +1,69 @@
+# ===========================================================================
+# http://www.gnu.org/software/autoconf-archive/ax_append_flag.html
+# ===========================================================================
+#
+# SYNOPSIS
+#
+# AX_APPEND_FLAG(FLAG, [FLAGS-VARIABLE])
+#
+# DESCRIPTION
+#
+# FLAG is appended to the FLAGS-VARIABLE shell variable, with a space
+# added in between.
+#
+# If FLAGS-VARIABLE is not specified, the current language's flags (e.g.
+# CFLAGS) is used. FLAGS-VARIABLE is not changed if it already contains
+# FLAG. If FLAGS-VARIABLE is unset in the shell, it is set to exactly
+# FLAG.
+#
+# NOTE: Implementation based on AX_CFLAGS_GCC_OPTION.
+#
+# LICENSE
+#
+# Copyright (c) 2008 Guido U. Draheim <guidod@gmx.de>
+# Copyright (c) 2011 Maarten Bosmans <mkbosmans@gmail.com>
+#
+# This program is free software: you can redistribute it and/or modify it
+# under the terms of the GNU General Public License as published by the
+# Free Software Foundation, either version 3 of the License, or (at your
+# option) any later version.
+#
+# This program 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 General
+# Public License for more details.
+#
+# You should have received a copy of the GNU General Public License along
+# with this program. If not, see <http://www.gnu.org/licenses/>.
+#
+# As a special exception, the respective Autoconf Macro's copyright owner
+# gives unlimited permission to copy, distribute and modify the configure
+# scripts that are the output of Autoconf when processing the Macro. You
+# need not follow the terms of the GNU General Public License when using
+# or distributing such scripts, even though portions of the text of the
+# Macro appear in them. The GNU General Public License (GPL) does govern
+# all other use of the material that constitutes the Autoconf Macro.
+#
+# This special exception to the GPL applies to versions of the Autoconf
+# Macro released by the Autoconf Archive. When you make and distribute a
+# modified version of the Autoconf Macro, you may extend this special
+# exception to the GPL to apply to your modified version as well.
+
+#serial 2
+
+AC_DEFUN([AX_APPEND_FLAG],
+[AC_PREREQ(2.59)dnl for _AC_LANG_PREFIX
+AS_VAR_PUSHDEF([FLAGS], [m4_default($2,_AC_LANG_PREFIX[FLAGS])])dnl
+AS_VAR_SET_IF(FLAGS,
+ [case " AS_VAR_GET(FLAGS) " in
+ *" $1 "*)
+ AC_RUN_LOG([: FLAGS already contains $1])
+ ;;
+ *)
+ AC_RUN_LOG([: FLAGS="$FLAGS $1"])
+ AS_VAR_SET(FLAGS, ["AS_VAR_GET(FLAGS) $1"])
+ ;;
+ esac],
+ [AS_VAR_SET(FLAGS,["$1"])])
+AS_VAR_POPDEF([FLAGS])dnl
+])dnl AX_APPEND_FLAG
diff --git a/m4/ax_cflags_warn_all.m4 b/m4/ax_cflags_warn_all.m4
index 7625580..c22e37f 100644
--- a/m4/ax_cflags_warn_all.m4
+++ b/m4/ax_cflags_warn_all.m4
@@ -25,6 +25,8 @@
# - $3 action-if-found : add value to shellvariable
# - $4 action-if-not-found : nothing
#
+# NOTE: These macros depend on AX_APPEND_FLAG.
+#
# LICENSE
#
# Copyright (c) 2008 Guido U. Draheim <guidod@gmx.de>
@@ -56,99 +58,14 @@
# modified version of the Autoconf Macro, you may extend this special
# exception to the GPL to apply to your modified version as well.
-#serial 10
+#serial 13
-AC_DEFUN([AX_CFLAGS_WARN_ALL],[dnl
-AS_VAR_PUSHDEF([FLAGS],[CFLAGS])dnl
-AS_VAR_PUSHDEF([VAR],[ac_cv_cflags_warn_all])dnl
+AC_DEFUN([AX_FLAGS_WARN_ALL],[dnl
+AS_VAR_PUSHDEF([FLAGS],[_AC_LANG_PREFIX[]FLAGS])dnl
+AS_VAR_PUSHDEF([VAR],[ac_cv_[]_AC_LANG_ABBREV[]flags_warn_all])dnl
AC_CACHE_CHECK([m4_ifval($1,$1,FLAGS) for maximum warnings],
VAR,[VAR="no, unknown"
- AC_LANG_PUSH([C])
- ac_save_[]FLAGS="$[]FLAGS"
-for ac_arg dnl
-in "-pedantic % -Wall" dnl GCC
- "-xstrconst % -v" dnl Solaris C
- "-std1 % -verbose -w0 -warnprotos" dnl Digital Unix
- "-qlanglvl=ansi % -qsrcmsg -qinfo=all:noppt:noppc:noobs:nocnd" dnl AIX
- "-ansi -ansiE % -fullwarn" dnl IRIX
- "+ESlit % +w1" dnl HP-UX C
- "-Xc % -pvctl[,]fullmsg" dnl NEC SX-5 (Super-UX 10)
- "-h conform % -h msglevel 2" dnl Cray C (Unicos)
- #
-do FLAGS="$ac_save_[]FLAGS "`echo $ac_arg | sed -e 's,%%.*,,' -e 's,%,,'`
- AC_COMPILE_IFELSE([AC_LANG_PROGRAM],
- [VAR=`echo $ac_arg | sed -e 's,.*% *,,'` ; break])
-done
- FLAGS="$ac_save_[]FLAGS"
- AC_LANG_POP([C])
-])
-case ".$VAR" in
- .ok|.ok,*) m4_ifvaln($3,$3) ;;
- .|.no|.no,*) m4_ifvaln($4,$4,[m4_ifval($2,[
- AC_RUN_LOG([: m4_ifval($1,$1,FLAGS)="$m4_ifval($1,$1,FLAGS) $2"])
- m4_ifval($1,$1,FLAGS)="$m4_ifval($1,$1,FLAGS) $2"])]) ;;
- *) m4_ifvaln($3,$3,[
- if echo " $[]m4_ifval($1,$1,FLAGS) " | grep " $VAR " 2>&1 >/dev/null
- then AC_RUN_LOG([: m4_ifval($1,$1,FLAGS) does contain $VAR])
- else AC_RUN_LOG([: m4_ifval($1,$1,FLAGS)="$m4_ifval($1,$1,FLAGS) $VAR"])
- m4_ifval($1,$1,FLAGS)="$m4_ifval($1,$1,FLAGS) $VAR"
- fi ]) ;;
-esac
-AS_VAR_POPDEF([VAR])dnl
-AS_VAR_POPDEF([FLAGS])dnl
-])
-
-dnl the only difference - the LANG selection... and the default FLAGS
-
-AC_DEFUN([AX_CXXFLAGS_WARN_ALL],[dnl
-AS_VAR_PUSHDEF([FLAGS],[CXXFLAGS])dnl
-AS_VAR_PUSHDEF([VAR],[ax_cv_cxxflags_warn_all])dnl
-AC_CACHE_CHECK([m4_ifval($1,$1,FLAGS) for maximum warnings],
-VAR,[VAR="no, unknown"
- AC_LANG_PUSH([C++])
- ac_save_[]FLAGS="$[]FLAGS"
-for ac_arg dnl
-in "-pedantic % -Wall" dnl GCC
- "-xstrconst % -v" dnl Solaris C
- "-std1 % -verbose -w0 -warnprotos" dnl Digital Unix
- "-qlanglvl=ansi % -qsrcmsg -qinfo=all:noppt:noppc:noobs:nocnd" dnl AIX
- "-ansi -ansiE % -fullwarn" dnl IRIX
- "+ESlit % +w1" dnl HP-UX C
- "-Xc % -pvctl[,]fullmsg" dnl NEC SX-5 (Super-UX 10)
- "-h conform % -h msglevel 2" dnl Cray C (Unicos)
- #
-do FLAGS="$ac_save_[]FLAGS "`echo $ac_arg | sed -e 's,%%.*,,' -e 's,%,,'`
- AC_COMPILE_IFELSE([AC_LANG_PROGRAM],
- [VAR=`echo $ac_arg | sed -e 's,.*% *,,'` ; break])
-done
- FLAGS="$ac_save_[]FLAGS"
- AC_LANG_POP([C++])
-])
-case ".$VAR" in
- .ok|.ok,*) m4_ifvaln($3,$3) ;;
- .|.no|.no,*) m4_ifvaln($4,$4,[m4_ifval($2,[
- AC_RUN_LOG([: m4_ifval($1,$1,FLAGS)="$m4_ifval($1,$1,FLAGS) $2"])
- m4_ifval($1,$1,FLAGS)="$m4_ifval($1,$1,FLAGS) $2"])]) ;;
- *) m4_ifvaln($3,$3,[
- if echo " $[]m4_ifval($1,$1,FLAGS) " | grep " $VAR " 2>&1 >/dev/null
- then AC_RUN_LOG([: m4_ifval($1,$1,FLAGS) does contain $VAR])
- else AC_RUN_LOG([: m4_ifval($1,$1,FLAGS)="$m4_ifval($1,$1,FLAGS) $VAR"])
- m4_ifval($1,$1,FLAGS)="$m4_ifval($1,$1,FLAGS) $VAR"
- fi ]) ;;
-esac
-AS_VAR_POPDEF([VAR])dnl
-AS_VAR_POPDEF([FLAGS])dnl
-])
-
-dnl the only difference - the LANG selection... and the default FLAGS
-
-AC_DEFUN([AX_FCFLAGS_WARN_ALL],[dnl
-AS_VAR_PUSHDEF([FLAGS],[FCFLAGS])dnl
-AS_VAR_PUSHDEF([VAR],[ax_cv_fcflags_warn_all])dnl
-AC_CACHE_CHECK([m4_ifval($1,$1,FLAGS) for maximum warnings],
-VAR,[VAR="no, unknown"
- AC_LANG_PUSH([Fortran])
- ac_save_[]FLAGS="$[]FLAGS"
+ac_save_[]FLAGS="$[]FLAGS"
for ac_arg dnl
in "-warn all % -warn all" dnl Intel
"-pedantic % -Wall" dnl GCC
@@ -164,25 +81,16 @@ do FLAGS="$ac_save_[]FLAGS "`echo $ac_arg | sed -e 's,%%.*,,' -e 's,%,,'`
AC_COMPILE_IFELSE([AC_LANG_PROGRAM],
[VAR=`echo $ac_arg | sed -e 's,.*% *,,'` ; break])
done
- FLAGS="$ac_save_[]FLAGS"
- AC_LANG_POP([Fortran])
+FLAGS="$ac_save_[]FLAGS"
])
+AS_VAR_POPDEF([FLAGS])dnl
case ".$VAR" in
.ok|.ok,*) m4_ifvaln($3,$3) ;;
- .|.no|.no,*) m4_ifvaln($4,$4,[m4_ifval($2,[
- AC_RUN_LOG([: m4_ifval($1,$1,FLAGS)="$m4_ifval($1,$1,FLAGS) $2"])
- m4_ifval($1,$1,FLAGS)="$m4_ifval($1,$1,FLAGS) $2"])]) ;;
- *) m4_ifvaln($3,$3,[
- if echo " $[]m4_ifval($1,$1,FLAGS) " | grep " $VAR " 2>&1 >/dev/null
- then AC_RUN_LOG([: m4_ifval($1,$1,FLAGS) does contain $VAR])
- else AC_RUN_LOG([: m4_ifval($1,$1,FLAGS)="$m4_ifval($1,$1,FLAGS) $VAR"])
- m4_ifval($1,$1,FLAGS)="$m4_ifval($1,$1,FLAGS) $VAR"
- fi ]) ;;
+ .|.no|.no,*) m4_default($4,[m4_ifval($2,[AX_APPEND_FLAG([$2], [$1])])]) ;;
+ *) m4_default($3,[AX_APPEND_FLAG([$VAR], [$1])]) ;;
esac
AS_VAR_POPDEF([VAR])dnl
-AS_VAR_POPDEF([FLAGS])dnl
-])
-
+])dnl AX_FLAGS_WARN_ALL
dnl implementation tactics:
dnl the for-argument contains a list of options. The first part of
dnl these does only exist to detect the compiler - usually it is
@@ -193,3 +101,21 @@ dnl like -Woption or -Xoption as they think of it is a pass-through
dnl to later compile stages or something. The "%" is used as a
dnl delimiter. A non-option comment can be given after "%%" marks
dnl which will be shown but not added to the respective C/CXXFLAGS.
+
+AC_DEFUN([AX_CFLAGS_WARN_ALL],[dnl
+AC_LANG_PUSH([C])
+AX_FLAGS_WARN_ALL([$1], [$2], [$3], [$4])
+AC_LANG_POP([C])
+])
+
+AC_DEFUN([AX_CXXFLAGS_WARN_ALL],[dnl
+AC_LANG_PUSH([C++])
+AX_FLAGS_WARN_ALL([$1], [$2], [$3], [$4])
+AC_LANG_POP([C++])
+])
+
+AC_DEFUN([AX_FCFLAGS_WARN_ALL],[dnl
+AC_LANG_PUSH([Fortran])
+AX_FLAGS_WARN_ALL([$1], [$2], [$3], [$4])
+AC_LANG_POP([Fortran])
+])
diff --git a/m4/ax_check_compiler_flags.m4 b/m4/ax_check_compile_flag.m4
index 35bfd2a..c3a8d69 100644
--- a/m4/ax_check_compiler_flags.m4
+++ b/m4/ax_check_compile_flag.m4
@@ -1,24 +1,31 @@
# ===========================================================================
-# http://www.gnu.org/software/autoconf-archive/ax_check_compiler_flags.html
+# http://www.gnu.org/software/autoconf-archive/ax_check_compile_flag.html
# ===========================================================================
#
# SYNOPSIS
#
-# AX_CHECK_COMPILER_FLAGS(FLAGS, [ACTION-SUCCESS], [ACTION-FAILURE])
+# AX_CHECK_COMPILE_FLAG(FLAG, [ACTION-SUCCESS], [ACTION-FAILURE], [EXTRA-FLAGS])
#
# DESCRIPTION
#
-# Check whether the given compiler FLAGS work with the current language's
-# compiler, or whether they give an error. (Warnings, however, are
-# ignored.)
+# Check whether the given FLAG works with the current language's compiler
+# or gives an error. (Warnings, however, are ignored)
#
# ACTION-SUCCESS/ACTION-FAILURE are shell commands to execute on
# success/failure.
#
+# If EXTRA-FLAGS is defined, it is added to the current language's default
+# flags (e.g. CFLAGS) when the check is done. The check is thus made with
+# the flags: "CFLAGS EXTRA-FLAGS FLAG". This can for example be used to
+# force the compiler to issue an error when a bad flag is given.
+#
+# NOTE: Implementation based on AX_CFLAGS_GCC_OPTION. Please keep this
+# macro in sync with AX_CHECK_{PREPROC,LINK}_FLAG.
+#
# LICENSE
#
-# Copyright (c) 2009 Steven G. Johnson <stevenj@alum.mit.edu>
-# Copyright (c) 2009 Matteo Frigo
+# Copyright (c) 2008 Guido U. Draheim <guidod@gmx.de>
+# Copyright (c) 2011 Maarten Bosmans <mkbosmans@gmail.com>
#
# This program is free software: you can redistribute it and/or modify it
# under the terms of the GNU General Public License as published by the
@@ -46,31 +53,20 @@
# modified version of the Autoconf Macro, you may extend this special
# exception to the GPL to apply to your modified version as well.
-#serial 9
+#serial 2
-AC_DEFUN([AX_CHECK_COMPILER_FLAGS],
-[AC_PREREQ(2.59) dnl for _AC_LANG_PREFIX
-AC_MSG_CHECKING([whether _AC_LANG compiler accepts $1])
-dnl Some hackery here since AC_CACHE_VAL can't handle a non-literal varname:
-AS_LITERAL_IF([$1],
- [AC_CACHE_VAL(AS_TR_SH(ax_cv_[]_AC_LANG_ABBREV[]_flags_[$1]), [
- ax_save_FLAGS=$[]_AC_LANG_PREFIX[]FLAGS
- _AC_LANG_PREFIX[]FLAGS="$1"
- AC_COMPILE_IFELSE([AC_LANG_PROGRAM()],
- AS_TR_SH(ax_cv_[]_AC_LANG_ABBREV[]_flags_[$1])=yes,
- AS_TR_SH(ax_cv_[]_AC_LANG_ABBREV[]_flags_[$1])=no)
- _AC_LANG_PREFIX[]FLAGS=$ax_save_FLAGS])],
- [ax_save_FLAGS=$[]_AC_LANG_PREFIX[]FLAGS
- _AC_LANG_PREFIX[]FLAGS="$1"
- AC_COMPILE_IFELSE([AC_LANG_PROGRAM()],
- eval AS_TR_SH(ax_cv_[]_AC_LANG_ABBREV[]_flags_[$1])=yes,
- eval AS_TR_SH(ax_cv_[]_AC_LANG_ABBREV[]_flags_[$1])=no)
- _AC_LANG_PREFIX[]FLAGS=$ax_save_FLAGS])
-eval ax_check_compiler_flags=$AS_TR_SH(ax_cv_[]_AC_LANG_ABBREV[]_flags_[$1])
-AC_MSG_RESULT($ax_check_compiler_flags)
-if test "x$ax_check_compiler_flags" = xyes; then
- m4_default([$2], :)
-else
- m4_default([$3], :)
-fi
-])dnl AX_CHECK_COMPILER_FLAGS
+AC_DEFUN([AX_CHECK_COMPILE_FLAG],
+[AC_PREREQ(2.59)dnl for _AC_LANG_PREFIX
+AS_VAR_PUSHDEF([CACHEVAR],[ax_cv_check_[]_AC_LANG_ABBREV[]flags_$4_$1])dnl
+AC_CACHE_CHECK([whether _AC_LANG compiler accepts $1], CACHEVAR, [
+ ax_check_save_flags=$[]_AC_LANG_PREFIX[]FLAGS
+ _AC_LANG_PREFIX[]FLAGS="$[]_AC_LANG_PREFIX[]FLAGS $4 $1"
+ AC_COMPILE_IFELSE([AC_LANG_PROGRAM()],
+ [AS_VAR_SET(CACHEVAR,[yes])],
+ [AS_VAR_SET(CACHEVAR,[no])])
+ _AC_LANG_PREFIX[]FLAGS=$ax_check_save_flags])
+AS_IF([test x"AS_VAR_GET(CACHEVAR)" = xyes],
+ [m4_default([$2], :)],
+ [m4_default([$3], :)])
+AS_VAR_POPDEF([CACHEVAR])dnl
+])dnl AX_CHECK_COMPILE_FLAGS
diff --git a/m4/ax_check_linker_flags.m4 b/m4/ax_check_link_flag.m4
index 894713c..e2d0d36 100644
--- a/m4/ax_check_linker_flags.m4
+++ b/m4/ax_check_link_flag.m4
@@ -1,26 +1,31 @@
# ===========================================================================
-# http://www.gnu.org/software/autoconf-archive/ax_check_linker_flags.html
+# http://www.gnu.org/software/autoconf-archive/ax_check_link_flag.html
# ===========================================================================
#
# SYNOPSIS
#
-# AX_CHECK_LINKER_FLAGS(FLAGS, [ACTION-SUCCESS], [ACTION-FAILURE])
+# AX_CHECK_LINK_FLAG(FLAG, [ACTION-SUCCESS], [ACTION-FAILURE], [EXTRA-FLAGS])
#
# DESCRIPTION
#
-# Check whether the given linker FLAGS work with the current language's
-# linker, or whether they give an error.
+# Check whether the given FLAG works with the linker or gives an error.
+# (Warnings, however, are ignored)
#
# ACTION-SUCCESS/ACTION-FAILURE are shell commands to execute on
# success/failure.
#
-# NOTE: Based on AX_CHECK_COMPILER_FLAGS.
+# If EXTRA-FLAGS is defined, it is added to the linker's default flags
+# when the check is done. The check is thus made with the flags: "LDFLAGS
+# EXTRA-FLAGS FLAG". This can for example be used to force the linker to
+# issue an error when a bad flag is given.
+#
+# NOTE: Implementation based on AX_CFLAGS_GCC_OPTION. Please keep this
+# macro in sync with AX_CHECK_{PREPROC,COMPILE}_FLAG.
#
# LICENSE
#
-# Copyright (c) 2009 Mike Frysinger <vapier@gentoo.org>
-# Copyright (c) 2009 Steven G. Johnson <stevenj@alum.mit.edu>
-# Copyright (c) 2009 Matteo Frigo
+# Copyright (c) 2008 Guido U. Draheim <guidod@gmx.de>
+# Copyright (c) 2011 Maarten Bosmans <mkbosmans@gmail.com>
#
# This program is free software: you can redistribute it and/or modify it
# under the terms of the GNU General Public License as published by the
@@ -48,30 +53,19 @@
# modified version of the Autoconf Macro, you may extend this special
# exception to the GPL to apply to your modified version as well.
-#serial 6
+#serial 2
-AC_DEFUN([AX_CHECK_LINKER_FLAGS],
-[AC_MSG_CHECKING([whether the linker accepts $1])
-dnl Some hackery here since AC_CACHE_VAL can't handle a non-literal varname:
-AS_LITERAL_IF([$1],
- [AC_CACHE_VAL(AS_TR_SH(ax_cv_linker_flags_[$1]), [
- ax_save_FLAGS=$LDFLAGS
- LDFLAGS="$1"
- AC_LINK_IFELSE([AC_LANG_PROGRAM()],
- AS_TR_SH(ax_cv_linker_flags_[$1])=yes,
- AS_TR_SH(ax_cv_linker_flags_[$1])=no)
- LDFLAGS=$ax_save_FLAGS])],
- [ax_save_FLAGS=$LDFLAGS
- LDFLAGS="$1"
- AC_LINK_IFELSE([AC_LANG_PROGRAM()],
- eval AS_TR_SH(ax_cv_linker_flags_[$1])=yes,
- eval AS_TR_SH(ax_cv_linker_flags_[$1])=no)
- LDFLAGS=$ax_save_FLAGS])
-eval ax_check_linker_flags=$AS_TR_SH(ax_cv_linker_flags_[$1])
-AC_MSG_RESULT($ax_check_linker_flags)
-if test "x$ax_check_linker_flags" = xyes; then
- m4_default([$2], :)
-else
- m4_default([$3], :)
-fi
-])dnl AX_CHECK_LINKER_FLAGS
+AC_DEFUN([AX_CHECK_LINK_FLAG],
+[AS_VAR_PUSHDEF([CACHEVAR],[ax_cv_check_ldflags_$4_$1])dnl
+AC_CACHE_CHECK([whether the linker accepts $1], CACHEVAR, [
+ ax_check_save_flags=$LDFLAGS
+ LDFLAGS="$LDFLAGS $4 $1"
+ AC_LINK_IFELSE([AC_LANG_PROGRAM()],
+ [AS_VAR_SET(CACHEVAR,[yes])],
+ [AS_VAR_SET(CACHEVAR,[no])])
+ LDFLAGS=$ax_check_save_flags])
+AS_IF([test x"AS_VAR_GET(CACHEVAR)" = xyes],
+ [m4_default([$2], :)],
+ [m4_default([$3], :)])
+AS_VAR_POPDEF([CACHEVAR])dnl
+])dnl AX_CHECK_LINK_FLAGS