[#1632] autoupdate

configure.ac

@@ -1,7 +1,7 @@
 #                                               -*- Autoconf -*-
 # Process this file with autoconf to produce a configure script.
 
-AC_PREREQ([2.69])
+AC_PREREQ([2.70])
 
 # For released versions, this is in x.y.z format.
 # For GIT versions, this is x.y.z-git, where x.y.z denotes the next development
@@ -339,7 +339,7 @@ esac
 
 werror_extras=
 AC_ARG_WITH(werror,
-    AC_HELP_STRING([--with-werror], [Compile using -Werror (default=no)]),
+    AS_HELP_STRING([--with-werror],[Compile using -Werror (default=no)]),
     [
      case "${withval}" in
          yes) with_werror=1 ;;
@@ -360,12 +360,10 @@ if test $with_werror = 1; then
    AC_MSG_CHECKING(for in-TU anonymous namespace breakage)
    # We use struct, not class, here, because some compilers complain about
    # "unused private members", causing a false positive.
-   AC_TRY_COMPILE([namespace { struct Foo {}; }
+   AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[namespace { struct Foo {}; }
-   namespace isc {struct Bar {Foo foo_;};} ],,
+   namespace isc {struct Bar {Foo foo_;};} ]], [[]])],[AC_MSG_RESULT(no)
-        [AC_MSG_RESULT(no)
          werror_ok=1
-         KEA_CXXFLAGS="$KEA_CXXFLAGS -Werror"],
+         KEA_CXXFLAGS="$KEA_CXXFLAGS -Werror"],[AC_MSG_RESULT(yes)])
-        [AC_MSG_RESULT(yes)])
    CXXFLAGS="$CXXFLAGS_SAVED"
 fi
 
@@ -398,8 +396,7 @@ fi                              dnl GXX = yes
 # allow building programs with static link.  we need to make it selective
 # because loadable modules cannot be statically linked.
 AC_ARG_ENABLE([static-link],
-AC_HELP_STRING([--enable-static-link],
+AS_HELP_STRING([--enable-static-link],[build programs with static link [[default=no]]]),
-  [build programs with static link [[default=no]]]),
   [enable_static_link=yes], [enable_static_link=no])
 AM_CONDITIONAL(USE_STATIC_LINK, test $enable_static_link = yes)
 AM_COND_IF([USE_STATIC_LINK], [AC_DEFINE([USE_STATIC_LINK], [1], [Was Kea statically linked?])])
@@ -435,16 +432,12 @@ case "$host" in
         # In OS X 10.9 (and possibly any future versions?) pthread_cond_destroy
         # doesn't work as documented, which makes some of unit tests fail.
         AC_MSG_CHECKING([OS X versions where destroying locked locks do not fail])
-        AC_TRY_COMPILE(
+        AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[#include <Availability.h>]], [[#ifdef __MAC_OS_X_VERSION_MIN_REQUIRED
-        [#include <Availability.h>],
-        [#ifdef __MAC_OS_X_VERSION_MIN_REQUIRED
          #if __MAC_OS_X_VERSION_MIN_REQUIRED >= 1090
          #error " OS X >= 10.9"
          #endif
          #endif
-         return 1;],
+         return 1;]])],[AC_MSG_RESULT([OS X < 10.9])],[AC_MSG_RESULT([OS X >= 10.9])
-        [AC_MSG_RESULT([OS X < 10.9])],
-        [AC_MSG_RESULT([OS X >= 10.9])
          kea_undefined_pthread_behavior=yes])
         ;;
 *-freebsd*)
@@ -480,8 +473,7 @@ case "$host" in
 esac
 
 # Made perfdhcp optional.
-AC_ARG_ENABLE(perfdhcp, [AC_HELP_STRING([--enable-perfdhcp],
+AC_ARG_ENABLE(perfdhcp, [AS_HELP_STRING([--enable-perfdhcp],[enable perfdhcp, a DHCP benchmarking tool [default=no]])],
-  [enable perfdhcp, a DHCP benchmarking tool [default=no]])],
   enable_perfdhcp=$enableval, enable_perfdhcp=no)
 
 DISTCHECK_PERFDHCP_CONFIGURE_FLAG=
@@ -589,17 +581,14 @@ AM_CONDITIONAL(OS_OPENBSD, test $BSD_TYPE = OpenBSD)
 
 
 AC_MSG_CHECKING(for sa_len in struct sockaddr)
-AC_TRY_COMPILE([
+AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
 #include <sys/types.h>
-#include <sys/socket.h>],
+#include <sys/socket.h>]], [[struct sockaddr sa; sa.sa_len = 0; return (0);]])],[AC_MSG_RESULT(yes)
-[struct sockaddr sa; sa.sa_len = 0; return (0);],
+        AC_DEFINE(HAVE_SA_LEN, 1, [Define to 1 if sockaddr has a sa_len member, and corresponding sin_len and sun_len])],[AC_MSG_RESULT(no)])
-        [AC_MSG_RESULT(yes)
-        AC_DEFINE(HAVE_SA_LEN, 1, [Define to 1 if sockaddr has a sa_len member, and corresponding sin_len and sun_len])],
-        AC_MSG_RESULT(no))
 
 usable_regex=
 AC_MSG_CHECKING(for usable C++11 regex)
-AC_TRY_RUN([
+AC_RUN_IFELSE([AC_LANG_SOURCE([[
 #include <regex>
 #include <iostream>
 int main() {
@@ -607,12 +596,9 @@ int main() {
   const std::string string = "This should match!";
   const auto result = std::regex_search(string, regex);
   return result ? EXIT_SUCCESS : EXIT_FAILURE;
-}],
+}]])],[AC_MSG_RESULT(yes)
-        [AC_MSG_RESULT(yes)
+         usable_regex="yes"],[AC_MSG_RESULT(no)
-         usable_regex="yes"],
+         usable_regex="no"],[AC_MSG_RESULT(cross compiling)])
-        [AC_MSG_RESULT(no)
-         usable_regex="no"],
-        [AC_MSG_RESULT(cross compiling)])
 # When cross-compiling we don't have any way to check if regex is
 # usable or not.
 # Let's be optimistic and assume it is by testing only the negative case.
@@ -652,8 +638,7 @@ defaultdirs="/usr /usr/local /usr/pkg /opt /opt/local"
 # the software is not built with MySQL support enabled.
 mysql_config="no"
 AC_ARG_WITH([mysql],
-  AC_HELP_STRING([--with-mysql=PATH],
+  AS_HELP_STRING([--with-mysql=PATH],[path to the MySQL 'mysql_config' script (MySQL is used for the DHCP database)]),
-    [path to the MySQL 'mysql_config' script (MySQL is used for the DHCP database)]),
     [mysql_config="$withval"])
 
 deprec_msg="no"
@@ -732,8 +717,7 @@ AM_CONDITIONAL(HAVE_MYSQL, test "$MYSQL_CONFIG" != "")
 
 pg_config="no"
 AC_ARG_WITH([pgsql],
-  AC_HELP_STRING([--with-pgsql=PATH],
+  AS_HELP_STRING([--with-pgsql=PATH],[path to the PostgreSQL 'pg_config' script]),
-    [path to the PostgreSQL 'pg_config' script]),
     [pg_config="$withval"])
 
 deprec_msg="no"
@@ -817,8 +801,7 @@ fi
 
 cql_config="no"
 AC_ARG_WITH([cql],
-  AC_HELP_STRING([--with-cql=PATH],
+  AS_HELP_STRING([--with-cql=PATH],[path to pkg-config or the Cassandra CQL 'cql_config' script]),
-    [path to pkg-config or the Cassandra CQL 'cql_config' script]),
     [cql_config="$withval"])
 
 if test "${cql_config}" = "yes" ; then
@@ -875,8 +858,7 @@ AM_CONDITIONAL(HAVE_CQL, test "$CQL_CONFIG" != "")
 DISTCHECK_SYSREPO_CONFIGURE_FLAG=
 sysrepo_config="no"
 AC_ARG_WITH([sysrepo],
-  AC_HELP_STRING([--with-sysrepo=PATH],
+  AS_HELP_STRING([--with-sysrepo=PATH],[path to pkg-config or the Sysrepo 'sysrepo_config' script]),
-    [path to pkg-config or the Sysrepo 'sysrepo_config' script]),
     [sysrepo_config="$withval"])
 
 if test "${sysrepo_config}" = "yes" ; then
@@ -986,8 +968,7 @@ AM_CONDITIONAL(HAVE_SYSREPO, test "$SYSREPO_CONFIG" != "")
 DISTCHECK_LOG4CPLUS_CONFIGURE_FLAG=
 log4cplus_path="yes"
 AC_ARG_WITH([log4cplus],
-  AC_HELP_STRING([--with-log4cplus=PATH],
+  AS_HELP_STRING([--with-log4cplus=PATH],[specify exact directory of log4cplus library and headers]),
-    [specify exact directory of log4cplus library and headers]),
     [log4cplus_path="$withval"])
 if test "${log4cplus_path}" = "no" ; then
     AC_MSG_ERROR([Need log4cplus])
@@ -1287,8 +1268,7 @@ AC_SUBST(PERL)
 AC_PATH_PROGS(AWK, gawk awk)
 AC_SUBST(AWK)
 
-AC_ARG_ENABLE(generate_messages, [AC_HELP_STRING([--enable-generate-messages],
+AC_ARG_ENABLE(generate_messages, [AS_HELP_STRING([--enable-generate-messages],[indicates that the messages files will be regenerated. [default=no]])],
-  [indicates that the messages files will be regenerated. [default=no]])],
   enable_generate_messages=$enableval, enable_generate_messages=no)
 
 AM_CONDITIONAL([GENERATE_MESSAGES], [test x$enable_generate_messages != xno])
@@ -1300,8 +1280,7 @@ if test "$cross_compiling" = "yes"; then
     fi
 fi
 
-AC_ARG_ENABLE(generate_parser, [AC_HELP_STRING([--enable-generate-parser],
+AC_ARG_ENABLE(generate_parser, [AS_HELP_STRING([--enable-generate-parser],[indicates that the parsers will be regenerated. This implies that the
-  [indicates that the parsers will be regenerated. This implies that the
    bison and flex are required [default=no]])],
    enable_generate_parser=$enableval, enable_generate_parser=no)
 
@@ -1350,13 +1329,11 @@ AM_CONDITIONAL([GENERATE_PARSER], [test x$enable_generate_parser != xno])
 # It may likely work with earlier versions, but 2.7 was the oldest one we tested
 # it with. We require python only if kea-shell was enabled. It is disabled
 # by default to not introduce hard dependency on python.
-AC_ARG_ENABLE(shell, [AC_HELP_STRING([--enable-shell],
+AC_ARG_ENABLE(shell, [AS_HELP_STRING([--enable-shell],[enable kea-shell, a text management client for Control Agent [default=no]])],
-  [enable kea-shell, a text management client for Control Agent [default=no]])],
   enable_shell=$enableval, enable_shell=no)
 
 
-AC_ARG_ENABLE(generate_docs, [AC_HELP_STRING([--enable-generate-docs],
+AC_ARG_ENABLE(generate_docs, [AS_HELP_STRING([--enable-generate-docs],[regenerate documentation using Sphinx [default=no]])],
-  [regenerate documentation using Sphinx [default=no]])],
   enable_generate_docs=$enableval, enable_generate_docs=no)
 
 
@@ -1372,8 +1349,7 @@ if test "x$enable_shell" != xno -o "x$enable_generate_docs" != xno; then
   AM_PATH_PYTHON([2.7])
 
   AC_ARG_WITH(site-packages,
-           AC_HELP_STRING([--with-site-packages],
+           AS_HELP_STRING([--with-site-packages],[place to install Kea Python module]),
-                          [place to install Kea Python module]),
            [pythondir=$withval;
             pkgpythondir=${pythondir}/$PACKAGE_NAME])
   if test "$pythondir" = "yes"; then
@@ -1423,11 +1399,11 @@ fi
 AM_CONDITIONAL(CA_TLS_TEST, test x$ca_tls_test != xno)
 
 AC_ARG_WITH([sphinx],
-  AC_HELP_STRING([--with-sphinx=PATH], [path to sphinx-build tool]),
+  AS_HELP_STRING([--with-sphinx=PATH],[path to sphinx-build tool]),
   [sphinx_path="$withval"])
 
 AC_ARG_WITH([pdflatex],
-  AC_HELP_STRING([--with-pdflatex=PATH], [path to pdflatex tool]),
+  AS_HELP_STRING([--with-pdflatex=PATH],[path to pdflatex tool]),
   [pdflatex_path="$withval"])
 PDFLATEX=no
 
@@ -1518,13 +1494,11 @@ AM_CONDITIONAL(HAVE_PDFLATEX, test "x$PDFLATEX" != "xno")
 AM_CONDITIONAL(GENERATE_DOCS, test x$enable_generate_docs != xno)
 
 AC_ARG_ENABLE(install-configurations,
-  [AC_HELP_STRING([--disable-install-configurations],
+  [AS_HELP_STRING([--disable-install-configurations],[do not install configuration])], install_configurations=$enableval, install_configurations=yes)
-  [do not install configuration])], install_configurations=$enableval, install_configurations=yes)
 
 AM_CONDITIONAL(INSTALL_CONFIGURATIONS, test x$install_configurations = xyes || test x$install_configurations = xtrue)
 
-AC_ARG_ENABLE(logger-checks, [AC_HELP_STRING([--enable-logger-checks],
+AC_ARG_ENABLE(logger-checks, [AS_HELP_STRING([--enable-logger-checks],[check logger messages [default=no]])], enable_logger_checks=$enableval, enable_logger_checks=no)
-  [check logger messages [default=no]])], enable_logger_checks=$enableval, enable_logger_checks=no)
 AM_CONDITIONAL(ENABLE_LOGGER_CHECKS, test x$enable_logger_checks != xno)
 AM_COND_IF([ENABLE_LOGGER_CHECKS], [AC_DEFINE([ENABLE_LOGGER_CHECKS], [1], [Check logger messages?])])
 
@@ -1552,8 +1526,7 @@ if test "x$VALGRIND" != "xno"; then
    found_valgrind="found"
 fi
 
-AC_ARG_ENABLE([fuzzing], [AC_HELP_STRING([--enable-fuzzing],
+AC_ARG_ENABLE([fuzzing], [AS_HELP_STRING([--enable-fuzzing],[indicates that the code will be built with AFL (American Fuzzy Lop) support.
-  [indicates that the code will be built with AFL (American Fuzzy Lop) support.
    Code built this way is unusable as a regular server. [default=no]])],
    [enable_fuzzing=$enableval], [enable_fuzzing=no])
 AM_CONDITIONAL([ENABLE_AFL], [test x$enable_fuzzing != xno])
@@ -1580,14 +1553,10 @@ fi
 # to reset internal state of getopt(). Failing to do so will result
 # in unpredictable output from getopt().
 AC_MSG_CHECKING([whether optreset variable is defined in unistd.h])
-AC_TRY_LINK(
+AC_LINK_IFELSE([AC_LANG_PROGRAM([[#include <unistd.h>]], [[extern int optreset; optreset=1;]])],[ AC_MSG_RESULT(yes)
-    [#include <unistd.h>],
+      var_optreset_exists=yes],[ AC_MSG_RESULT(no)
-    [extern int optreset; optreset=1;],
+      var_optreset_exists=no
-    [ AC_MSG_RESULT(yes)
+])
-      var_optreset_exists=yes],
-    [ AC_MSG_RESULT(no)
-      var_optreset_exists=no]
-)
 AM_CONDITIONAL(HAVE_OPTRESET, test "x$var_optreset_exists" != "xno")
 AM_COND_IF([HAVE_OPTRESET], [AC_DEFINE([HAVE_OPTRESET], [1], [Check for optreset?])])
 

m4macros/ax_boost_for_kea.m4

@@ -50,8 +50,7 @@ boost_lib_path=
 #
 # If explicitly specified, use it.
 AC_ARG_WITH([boost-include],
-  AC_HELP_STRING([--with-boost-include=PATH],
+  AS_HELP_STRING([--with-boost-include=PATH],[specify exact directory for Boost headers]),
-    [specify exact directory for Boost headers]),
     [boost_include_path="$withval"])
 # If not specified, try some common paths.
 if test -z "$with_boost_include"; then
@@ -88,12 +87,11 @@ AC_CHECK_HEADERS(boost/integer/common_factor.hpp)
 # the code and we'll end up using the system header rather than the boost. For
 # example, if your boost headers are in /usr/local/include/boost, you should
 # use --with-boost-include=/usr/local/include
-AC_TRY_COMPILE([
+AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
 #include <regex.h>
 #ifdef BOOST_RE_REGEX_H
 #error "boost/regex.h"
-#endif],,,
+#endif]], [[]])],[],[AC_MSG_ERROR([${boost_include_path}/regex.h is used in place of /usr/include/regex.h: when specifying path to boost, please omit the /boost at the end of the include path.])])
-[AC_MSG_ERROR([${boost_include_path}/regex.h is used in place of /usr/include/regex.h: when specifying path to boost, please omit the /boost at the end of the include path.])])
 
 # clang can cause false positives with -Werror without -Qunused-arguments.
 # it can be triggered if used with ccache.
@@ -104,26 +102,22 @@ AC_CHECK_DECL([__clang__], [CLANG_CXXFLAGS="-Qunused-arguments"], [])
 # may depend on preceding header files, and if inconsistency happens
 # it could lead to a critical disruption.
 AC_MSG_CHECKING([whether Boost tries to use threads])
-AC_TRY_COMPILE([
+AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
 #include <boost/config.hpp>
 #ifdef BOOST_HAS_THREADS
 #error "boost will use threads"
-#endif],,
+#endif]], [[]])],[AC_MSG_RESULT(no)
-[AC_MSG_RESULT(no)
+ CPPFLAGS_BOOST_THREADCONF="-DBOOST_DISABLE_THREADS=1"],[AC_MSG_RESULT(yes)])
- CPPFLAGS_BOOST_THREADCONF="-DBOOST_DISABLE_THREADS=1"],
-[AC_MSG_RESULT(yes)])
 
 # Boost offset_ptr is known to not compile on some platforms, depending on
 # boost version, its local configuration, and compiler.  Detect it.
 CXXFLAGS_SAVED="$CXXFLAGS"
 CXXFLAGS="$CXXFLAGS $CLANG_CXXFLAGS -Werror"
 AC_MSG_CHECKING([Boost offset_ptr compiles])
-AC_TRY_COMPILE([
+AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
 #include <boost/interprocess/offset_ptr.hpp>
-],,
+]], [[]])],[AC_MSG_RESULT(yes)
-[AC_MSG_RESULT(yes)
+ BOOST_OFFSET_PTR_WOULDFAIL=no],[AC_MSG_RESULT(no)
- BOOST_OFFSET_PTR_WOULDFAIL=no],
-[AC_MSG_RESULT(no)
  BOOST_OFFSET_PTR_WOULDFAIL=yes])
 CXXFLAGS="$CXXFLAGS_SAVED"
 
@@ -134,13 +128,12 @@ if test "X$GXX" = "Xyes"; then
    CXXFLAGS="$CXXFLAGS $CLANG_CXXFLAGS -Werror"
 
    AC_MSG_CHECKING([Boost numeric_cast compiles with -Werror])
-   AC_TRY_COMPILE([
+   AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
    #include <boost/numeric/conversion/cast.hpp>
-   ],[
+   ]], [[
    return (boost::numeric_cast<short>(0));
-   ],[AC_MSG_RESULT(yes)
+   ]])],[AC_MSG_RESULT(yes)
-      BOOST_NUMERIC_CAST_WOULDFAIL=no],
+      BOOST_NUMERIC_CAST_WOULDFAIL=no],[AC_MSG_RESULT(no)
-   [AC_MSG_RESULT(no)
     BOOST_NUMERIC_CAST_WOULDFAIL=yes])
 
    CXXFLAGS="$CXXFLAGS_SAVED"
@@ -152,26 +145,22 @@ fi
 # BOOST_STATIC_ASSERT in versions below Boost 1.54.0 is known to result
 # in warnings with GCC 4.8.  Detect it.
 AC_MSG_CHECKING([BOOST_STATIC_ASSERT compiles])
-AC_TRY_COMPILE([
+AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
 #include <boost/static_assert.hpp>
 void testfn(void) { BOOST_STATIC_ASSERT(true); }
-],,
+]], [[]])],[AC_MSG_RESULT(yes)
-[AC_MSG_RESULT(yes)
+ BOOST_STATIC_ASSERT_WOULDFAIL=no],[AC_MSG_RESULT(no)
- BOOST_STATIC_ASSERT_WOULDFAIL=no],
-[AC_MSG_RESULT(no)
  BOOST_STATIC_ASSERT_WOULDFAIL=yes])
 
 # Get libs when explicitly configured
 AC_ARG_WITH([boost-libs],
-  AC_HELP_STRING([--with-boost-libs=SPEC],
+  AS_HELP_STRING([--with-boost-libs=SPEC],[specify Boost libraries to link with, e.g., '-lboost_system']),
-    [specify Boost libraries to link with, e.g., '-lboost_system']),
     [BOOST_LIBS="$withval"
      DISTCHECK_BOOST_CONFIGURE_FLAG="$DISTCHECK_BOOST_CONFIGURE_FLAG --with-boost-libs=$withval"])
 
 # Get lib dir when explicitly configured
 AC_ARG_WITH([boost-lib-dir],
-  AC_HELP_STRING([--with-boost-lib-dir=PATH],
+  AS_HELP_STRING([--with-boost-lib-dir=PATH],[specify directory where to find Boost libraries]),
-    [specify directory where to find Boost libraries]),
     [BOOST_LIB_DIR="$withval"
      DISTCHECK_BOOST_CONFIGURE_FLAG="$DISTCHECK_BOOST_CONFIGURE_FLAG --with-boost-lib-dir=$withval"])
 
@@ -192,11 +181,9 @@ if test "x${BOOST_LIBS}" = "x"; then
    CPPFLAGS="$CPPFLAGS -DBOOST_ERROR_CODE_HEADER_ONLY"
    CPPFLAGS="$CPPFLAGS -DBOOST_SYSTEM_NO_DEPRECATED"
 
-   AC_TRY_COMPILE([
+   AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
    #include <boost/system/error_code.hpp>
-   ],,
+   ]], [[]])],[AC_MSG_RESULT(yes)],[AC_MSG_RESULT(no)
-   [AC_MSG_RESULT(yes)],
-   [AC_MSG_RESULT(no)
     AC_MSG_WARN([The Boost system library is required.])
     BOOST_LIBS="-lboost_system"
     if test "x${BOOST_LIB_DIR}" = "x"; then

m4macros/ax_crypto.m4

@@ -94,8 +94,7 @@ if test "${use_openssl}" != "auto" -a "${use_openssl}" != "no" ; then
    botan_config="no"
 fi
 AC_ARG_WITH([botan-config],
-  AC_HELP_STRING([--with-botan-config=PATH],
+  AS_HELP_STRING([--with-botan-config=PATH],[specify the path to the botan-config script]),
-    [specify the path to the botan-config script]),
     [botan_config="$withval"])
 distcheck_botan="--with-botan-config=$botan_config"
 if test "${botan_config}" = "no" ; then

m4macros/ax_isc_rpath.m4

@@ -15,7 +15,7 @@ dnl If you pass --disable-rpath to configure, ISC_RPATH_FLAG is not set
 AC_DEFUN([AX_ISC_RPATH], [
 
 AC_ARG_ENABLE(rpath,
-    [AC_HELP_STRING([--disable-rpath], [don't hardcode library path into binaries])],
+    [AS_HELP_STRING([--disable-rpath],[don't hardcode library path into binaries])],
     rpath=$enableval, rpath=yes)
 
 if test x$rpath != xno; then
@@ -33,11 +33,10 @@ if test x$rpath != xno; then
 
     # check -Wl,-R and -R rather than gcc specific -rpath to be as portable
     # as possible.  -Wl,-R seems to be safer, so we try it first.  In some
-    # cases -R is not actually recognized but AC_TRY_LINK doesn't fail due to
+    # cases -R is not actually recognized but AC_LINK_IFELSE([AC_LANG_PROGRAM([[]], [[]])],[],[]) doesn't fail due to
     # that.
     AC_MSG_CHECKING([whether -Wl,-R flag is available in linker])
-    AC_TRY_LINK([],[],
+    AC_LINK_IFELSE([AC_LANG_PROGRAM([[]], [[]])],[ AC_MSG_RESULT(yes)
-        [ AC_MSG_RESULT(yes)
             ISC_RPATH_FLAG=-Wl,-R
         ],[ AC_MSG_RESULT(no)
             AC_MSG_CHECKING([whether -R flag is available in linker])
@@ -49,7 +48,7 @@ if test x$rpath != xno; then
             # up, is to use -Werror.
             CXXFLAGS="$CXXFLAGS_SAVED -R/usr/lib"
             CCFLAGS="$CCFLAGS_SAVED -R/usr/lib"
-        AC_TRY_LINK([], [],
+        _au_m4_changequote([,])AC_TRY_LINK([], [],
             [ AC_MSG_RESULT([yes; note that -R is more sensitive about the position in option arguments])
                 ISC_RPATH_FLAG=-R
             ],[ AC_MSG_RESULT(no) ])