3 dnl Version not hardcoded here. Fetched later from ares_version.h
5 [c-ares mailing list => http://cool.haxx.se/mailman/listinfo/c-ares])
7 AC_CONFIG_SRCDIR([ares_ipv6.h])
8 AM_CONFIG_HEADER([config.h])
11 CARES_CHECK_OPTION_DEBUG
12 CARES_CHECK_OPTION_OPTIMIZE
13 CARES_CHECK_OPTION_WARNINGS
15 dnl SED is mandatory for configure process and libtool.
16 dnl Set it now, allowing it to be changed later.
17 AC_PATH_PROG([SED], [sed], [not_found],
18 [$PATH:/usr/bin:/usr/local/bin])
19 if test -z "$SED" || test "$SED" = "not_found"; then
20 AC_MSG_ERROR([sed not found in PATH. Cannot continue without sed.])
24 dnl GREP is mandatory for configure process and libtool.
25 dnl Set it now, allowing it to be changed later.
26 AC_PATH_PROG([GREP], [grep], [not_found],
27 [$PATH:/usr/bin:/usr/local/bin])
28 if test -z "$GREP" || test "$GREP" = "not_found"; then
29 AC_MSG_ERROR([grep not found in PATH. Cannot continue without grep.])
33 dnl EGREP is mandatory for configure process and libtool.
34 dnl Set it now, allowing it to be changed later.
35 if echo a | ($GREP -E '(a|b)') >/dev/null 2>&1; then
36 AC_MSG_CHECKING([for egrep])
38 AC_MSG_RESULT([$EGREP])
40 AC_PATH_PROG([EGREP], [egrep], [not_found],
41 [$PATH:/usr/bin:/usr/local/bin])
43 if test -z "$EGREP" || test "$EGREP" = "not_found"; then
44 AC_MSG_ERROR([egrep not found in PATH. Cannot continue without egrep.])
48 dnl AR is mandatory for configure process and libtool.
49 dnl This is target dependant, so check it as a tool.
50 AC_PATH_TOOL([AR], [ar], [not_found],
51 [$PATH:/usr/bin:/usr/local/bin])
52 if test -z "$AR" || test "$AR" = "not_found"; then
53 AC_MSG_ERROR([ar not found in PATH. Cannot continue without ar.])
57 dnl Fetch c-ares version from ares_version.h
58 VERSION=`$SED -ne 's/^#define ARES_VERSION_STR "\(.*\)"/\1/p' ${srcdir}/ares_version.h`
59 AM_INIT_AUTOMAKE([c-ares], [$VERSION])
60 AC_MSG_CHECKING([c-ares version])
61 AC_MSG_RESULT([$VERSION])
64 dnl Detect the canonical host and target build environment
68 dnl Get system canonical name
69 AC_DEFINE_UNQUOTED(OS, "${host}", [cpu-machine-OS])
75 dnl This defines _ALL_SOURCE for AIX
76 CARES_CHECK_AIX_ALL_SOURCE
78 dnl Our configure and build reentrant settings
79 CARES_CONFIGURE_REENTRANT
81 dnl check for how to do large files
86 AC_DEFINE(ETC_INET, 1, [if a /etc/inet dir is being used])
90 dnl support building of Windows DLLs
93 CARES_PROCESS_DEBUG_BUILD_OPTS
95 AM_CONDITIONAL(DEBUGBUILD, test x$want_debug = xyes)
96 AM_CONDITIONAL(CURLDEBUG, test x$want_debug = xyes)
98 dnl skip libtool C++ and Fortran compiler checks
99 m4_ifdef([AC_PROG_CXX], [m4_undefine([AC_PROG_CXX])])
100 m4_defun([AC_PROG_CXX],[])
101 m4_ifdef([AC_PROG_CXXCPP], [m4_undefine([AC_PROG_CXXCPP])])
102 m4_defun([AC_PROG_CXXCPP],[true])
103 m4_ifdef([AC_PROG_F77], [m4_undefine([AC_PROG_F77])])
104 m4_defun([AC_PROG_F77],[])
106 dnl skip libtool C++ and Fortran linker checks
107 m4_ifdef([AC_LIBTOOL_CXX], [m4_undefine([AC_LIBTOOL_CXX])])
108 m4_defun([AC_LIBTOOL_CXX],[])
109 m4_ifdef([AC_LIBTOOL_CXXCPP], [m4_undefine([AC_LIBTOOL_CXXCPP])])
110 m4_defun([AC_LIBTOOL_CXXCPP],[true])
111 m4_ifdef([AC_LIBTOOL_F77], [m4_undefine([AC_LIBTOOL_F77])])
112 m4_defun([AC_LIBTOOL_F77],[])
114 dnl force libtool to build static libraries with PIC on AMD64-Linux & FreeBSD
115 AC_MSG_CHECKING([if arch-OS host is AMD64-Linux/FreeBSD (to build static libraries with PIC)])
117 x86_64*linux*|amd64*freebsd*|ia64*freebsd*)
129 AC_MSG_CHECKING([if we need -no-undefined])
131 *-*-cygwin* | *-*-mingw* | *-*-pw32* | *-*-cegcc*)
132 need_no_undefined=yes
138 AC_MSG_RESULT($need_no_undefined)
139 AM_CONDITIONAL(NO_UNDEFINED, test x$need_no_undefined = xyes)
141 dnl **********************************************************************
142 dnl platform/compiler/architecture specific checks/flags
143 dnl **********************************************************************
146 CARES_SET_COMPILER_BASIC_OPTS
147 CARES_SET_COMPILER_DEBUG_OPTS
148 CARES_SET_COMPILER_OPTIMIZE_OPTS
149 CARES_SET_COMPILER_WARNING_OPTS
153 x86_64*linux*|amd64*freebsd*|ia64*freebsd*)
155 if test "$compiler_id" = "INTEL_UNIX_C"; then
157 if test "$compiler_num" -ge "900" &&
158 test "$compiler_num" -lt "1000"; then
160 CFLAGS="$CFLAGS -i-dynamic"
163 if test "$compiler_num" -ge "1000"; then
164 dnl icc 10.X or later
165 CFLAGS="$CFLAGS -shared-intel"
173 CURL_CHECK_COMPILER_HALT_ON_ERROR
174 CURL_CHECK_COMPILER_ARRAY_SIZE_NEGATIVE
176 dnl **********************************************************************
177 dnl Compilation based checks should not be done before this point.
178 dnl **********************************************************************
180 dnl **********************************************************************
181 dnl Make sure that our checks for headers windows.h winsock.h winsock2.h
182 dnl and ws2tcpip.h take precedence over any other further checks which
183 dnl could be done later using AC_CHECK_HEADER or AC_CHECK_HEADERS for
184 dnl this specific header files. And do them before its results are used.
185 dnl **********************************************************************
187 CURL_CHECK_HEADER_WINDOWS
188 CURL_CHECK_NATIVE_WINDOWS
189 case X-"$ac_cv_native_windows" in
191 CURL_CHECK_HEADER_WINSOCK
192 CURL_CHECK_HEADER_WINSOCK2
193 CURL_CHECK_HEADER_WS2TCPIP
196 ac_cv_header_winsock_h="no"
197 ac_cv_header_winsock2_h="no"
198 ac_cv_header_ws2tcpip_h="no"
202 dnl **********************************************************************
203 dnl Checks for libraries.
204 dnl **********************************************************************
206 dnl gethostbyname without lib or in the nsl lib?
207 AC_CHECK_FUNC(gethostbyname,
208 [HAVE_GETHOSTBYNAME="1"
210 [ AC_CHECK_LIB(nsl, gethostbyname,
211 [HAVE_GETHOSTBYNAME="1"
216 if test "$HAVE_GETHOSTBYNAME" != "1"
218 dnl gethostbyname in the socket lib?
219 AC_CHECK_LIB(socket, gethostbyname,
220 [HAVE_GETHOSTBYNAME="1"
221 LIBS="$LIBS -lsocket"
225 dnl At least one system has been identified to require BOTH nsl and socket
226 dnl libs at the same time to link properly.
227 if test "$HAVE_GETHOSTBYNAME" != "1"
229 AC_MSG_CHECKING([for gethostbyname with both nsl and socket libs])
230 my_ac_save_LIBS=$LIBS
231 LIBS="-lnsl -lsocket $LIBS"
239 HAVE_GETHOSTBYNAME="1"
242 LIBS=$my_ac_save_LIBS
246 if test "$HAVE_GETHOSTBYNAME" != "1"
248 dnl This is for winsock systems
249 if test "$ac_cv_header_windows_h" = "yes"; then
250 if test "$ac_cv_header_winsock_h" = "yes"; then
253 winsock_LIB="-lwinsock"
256 winsock_LIB="-lwsock32"
260 if test "$ac_cv_header_winsock2_h" = "yes"; then
261 winsock_LIB="-lws2_32"
263 if test ! -z "$winsock_LIB"; then
264 my_ac_save_LIBS=$LIBS
265 LIBS="$winsock_LIB $LIBS"
266 AC_MSG_CHECKING([for gethostbyname in $winsock_LIB])
269 #ifdef HAVE_WINDOWS_H
270 #ifndef WIN32_LEAN_AND_MEAN
271 #define WIN32_LEAN_AND_MEAN
274 #ifdef HAVE_WINSOCK2_H
275 #include <winsock2.h>
277 #ifdef HAVE_WINSOCK_H
283 gethostbyname("www.dummysite.com");
287 HAVE_GETHOSTBYNAME="1"
291 LIBS=$my_ac_save_LIBS
297 if test "$HAVE_GETHOSTBYNAME" != "1"
299 dnl This is for Minix 3.1
300 AC_MSG_CHECKING([for gethostbyname for Minix 3])
303 /* Older Minix versions may need <net/gen/netdb.h> here instead */
306 gethostbyname("www.dummysite.com");
310 HAVE_GETHOSTBYNAME="1"
316 if test "$HAVE_GETHOSTBYNAME" != "1"
318 dnl This is for eCos with a stubbed DNS implementation
319 AC_MSG_CHECKING([for gethostbyname for eCos])
325 gethostbyname("www.dummysite.com");
329 HAVE_GETHOSTBYNAME="1"
335 if test "$HAVE_GETHOSTBYNAME" != "1"
337 dnl gethostbyname in the net lib - for BeOS
338 AC_CHECK_LIB(net, gethostbyname,
339 [HAVE_GETHOSTBYNAME="1"
345 if test "$HAVE_GETHOSTBYNAME" = "1"; then
346 AC_DEFINE(HAVE_GETHOSTBYNAME, 1, [If you have gethostbyname])
348 AC_MSG_ERROR([couldn't find libraries for gethostbyname()])
352 AC_CHECK_FUNC(strcasecmp, , [ AC_CHECK_LIB(resolve, strcasecmp) ])
354 if test "$ac_cv_lib_resolve_strcasecmp" = "$ac_cv_func_strcasecmp"; then
355 AC_CHECK_LIB(resolve, strcasecmp,
356 [LIBS="-lresolve $LIBS"],
360 ac_cv_func_strcasecmp="no"
363 AC_CHECK_FUNC(connect, , [ AC_CHECK_LIB(socket, connect) ])
365 dnl **********************************************************************
366 dnl In case that function clock_gettime with monotonic timer is available,
367 dnl check for additional required libraries.
368 dnl **********************************************************************
369 CURL_CHECK_LIBS_CLOCK_GETTIME_MONOTONIC
371 AC_MSG_CHECKING([whether to use libgcc])
372 AC_ARG_ENABLE(libgcc,
373 AC_HELP_STRING([--enable-libgcc],[use libgcc when linking]),
374 [ case "$enableval" in
386 dnl Default is to try the thread-safe versions of a few functions
389 dnl detect AIX 4.3 or later
390 AC_MSG_CHECKING([AIX 4.3 or later])
392 #if defined(_AIX) && defined(_AIX43)
395 #error "this is not AIX 4.3 or later"
398 [ AC_MSG_RESULT([yes])
401 [ AC_MSG_RESULT([no]) ]
404 AC_ARG_ENABLE(thread,dnl
405 AC_HELP_STRING([--disable-thread],[don't look for thread-safe functions])
406 AC_HELP_STRING([--enable-thread],[look for thread-safe functions]),
407 [ case "$enableval" in
410 AC_MSG_WARN(c-ares will not get built using thread-safe functions)
418 if test X"$OPT_THREAD" = Xoff
420 AC_DEFINE(DISABLED_THREADSAFE, 1,
421 [Set to explicitly specify we don't want to use thread-safe functions])
424 dnl for recent AIX versions, we skip all the thread-safe checks above since
425 dnl they claim a thread-safe libc using the standard API. But there are
426 dnl some functions still not thread-safe. Check for these!
428 dnl Let's hope this split URL remains working:
429 dnl http://publibn.boulder.ibm.com/doc_link/en_US/a_doc_lib/aixprggd/ \
430 dnl genprogc/thread_quick_ref.htm
432 if test "x$RECENTAIX" = "xyes"; then
434 AC_DEFINE(_THREAD_SAFE, 1, [define this if you need it to compile thread-safe code])
439 dnl **********************************************************************
440 dnl Back to "normal" configuring
441 dnl **********************************************************************
443 dnl Checks for header files.
446 CURL_CHECK_HEADER_MALLOC
448 dnl check for a few basic system headers we need
466 arpa/nameser_compat.h \
468 dnl to do if not found
474 #ifdef HAVE_SYS_TYPES_H
475 #include <sys/types.h>
477 #ifdef HAVE_SYS_TIME_H
478 #include <sys/time.h>
480 dnl We do this default-include simply to make sure that the nameser_compat.h
481 dnl header *REALLY* can be include after the new nameser.h. It seems AIX 5.1
482 dnl (and others?) is not designed to allow this.
483 #ifdef HAVE_ARPA_NAMESER_H
484 #include <arpa/nameser.h>
487 dnl *Sigh* these are needed in order for net/if.h to get properly detected.
488 #ifdef HAVE_SYS_SOCKET_H
489 #include <sys/socket.h>
491 #ifdef HAVE_NETINET_IN_H
492 #include <netinet/in.h>
497 dnl Checks for typedefs, structures, and compiler characteristics.
501 CURL_CHECK_STRUCT_TIMEVAL
503 AC_CHECK_SIZEOF(size_t)
504 AC_CHECK_SIZEOF(long)
505 AC_CHECK_SIZEOF(time_t)
507 AC_CHECK_TYPE(long long,
508 [AC_DEFINE(HAVE_LONGLONG, 1,
509 [Define to 1 if the compiler supports the 'long long' data type.])]
513 if test "xyes" = "x$longlong"; then
514 AC_MSG_CHECKING([if numberLL works])
515 AC_COMPILE_IFELSE([long long val = 1000LL;],
516 [AC_DEFINE(HAVE_LL, 1, [if your compiler supports LL])]
524 AC_CHECK_TYPE(ssize_t, ,
525 AC_DEFINE(ssize_t, int, [the signed version of size_t]))
527 # check for bool type
528 AC_CHECK_TYPE([bool],[
529 AC_DEFINE(HAVE_BOOL_T, 1,
530 [Define to 1 if bool is an available type.])
532 #ifdef HAVE_SYS_TYPES_H
533 #include <sys/types.h>
535 #ifdef HAVE_STDBOOL_H
540 # Check for socklen_t or equivalent
541 CURL_CHECK_TYPE_SOCKLEN_T
545 TYPE_SOCKADDR_STORAGE
552 CURL_CHECK_FUNC_RECVFROM
554 CURL_CHECK_MSG_NOSIGNAL
556 CARES_CHECK_FUNC_GETADDRINFO
557 CARES_CHECK_FUNC_GETADDRINFO_UNFREEABLE_AI_ADDR
558 CARES_CHECK_FUNC_GETHOSTNAME
559 CARES_CHECK_FUNC_GETSERVBYPORT_R
560 CARES_CHECK_FUNC_INET_NTOP
561 CARES_CHECK_FUNC_INET_PTON
562 CARES_CHECK_FUNC_STRCASECMP
563 CARES_CHECK_FUNC_STRCMPI
564 CARES_CHECK_FUNC_STRDUP
565 CARES_CHECK_FUNC_STRICMP
566 CARES_CHECK_FUNC_STRNCASECMP
567 CARES_CHECK_FUNC_STRNCMPI
568 CARES_CHECK_FUNC_STRNICMP
569 CARES_CHECK_FUNC_WRITEV
572 dnl check for AF_INET6
573 CARES_CHECK_CONSTANT(
576 #ifdef HAVE_WINDOWS_H
577 #ifndef WIN32_LEAN_AND_MEAN
578 #define WIN32_LEAN_AND_MEAN
581 #ifdef HAVE_WINSOCK2_H
582 #include <winsock2.h>
585 #ifdef HAVE_SYS_TYPES_H
586 #include <sys/types.h>
588 #ifdef HAVE_SYS_SOCKET_H
589 #include <sys/socket.h>
593 AC_DEFINE_UNQUOTED(HAVE_PF_INET6,1,[Define to 1 if you have PF_INET6.])
596 dnl check for PF_INET6
597 CARES_CHECK_CONSTANT(
600 #ifdef HAVE_WINDOWS_H
601 #ifndef WIN32_LEAN_AND_MEAN
602 #define WIN32_LEAN_AND_MEAN
605 #ifdef HAVE_WINSOCK2_H
606 #include <winsock2.h>
609 #ifdef HAVE_SYS_TYPES_H
610 #include <sys/types.h>
612 #ifdef HAVE_SYS_SOCKET_H
613 #include <sys/socket.h>
617 AC_DEFINE_UNQUOTED(HAVE_AF_INET6,1,[Define to 1 if you have AF_INET6.])
621 dnl check for the in6_addr structure
625 #ifdef HAVE_WINDOWS_H
626 #ifndef WIN32_LEAN_AND_MEAN
627 #define WIN32_LEAN_AND_MEAN
630 #ifdef HAVE_WINSOCK2_H
631 #include <winsock2.h>
632 #ifdef HAVE_WS2TCPIP_H
633 #include <ws2tcpip.h>
637 #ifdef HAVE_SYS_TYPES_H
638 #include <sys/types.h>
640 #ifdef HAVE_NETINET_IN_H
641 #include <netinet/in.h>
645 AC_DEFINE_UNQUOTED(HAVE_STRUCT_IN6_ADDR,1,[Define to 1 if you have struct in6_addr.])
648 dnl check for the sockaddr_in6 structure
652 #ifdef HAVE_WINDOWS_H
653 #ifndef WIN32_LEAN_AND_MEAN
654 #define WIN32_LEAN_AND_MEAN
657 #ifdef HAVE_WINSOCK2_H
658 #include <winsock2.h>
659 #ifdef HAVE_WS2TCPIP_H
660 #include <ws2tcpip.h>
664 #ifdef HAVE_SYS_TYPES_H
665 #include <sys/types.h>
667 #ifdef HAVE_NETINET_IN_H
668 #include <netinet/in.h>
672 AC_DEFINE_UNQUOTED(HAVE_STRUCT_SOCKADDR_IN6,1,
673 [Define to 1 if you have struct sockaddr_in6.]) ac_have_sockaddr_in6=yes
676 AC_CHECK_MEMBER(struct sockaddr_in6.sin6_scope_id,
677 AC_DEFINE_UNQUOTED(HAVE_SOCKADDR_IN6_SIN6_SCOPE_ID,1,
678 [Define to 1 if your struct sockaddr_in6 has sin6_scope_id.])
682 #ifdef HAVE_WINDOWS_H
683 #ifndef WIN32_LEAN_AND_MEAN
684 #define WIN32_LEAN_AND_MEAN
687 #ifdef HAVE_WINSOCK2_H
688 #include <winsock2.h>
689 #ifdef HAVE_WS2TCPIP_H
690 #include <ws2tcpip.h>
694 #ifdef HAVE_SYS_TYPES_H
695 #include <sys/types.h>
697 #ifdef HAVE_NETINET_IN_H
698 #include <netinet/in.h>
703 dnl check for the addrinfo structure
704 AC_CHECK_MEMBER(struct addrinfo.ai_flags,
705 AC_DEFINE_UNQUOTED(HAVE_STRUCT_ADDRINFO,1,
706 [Define to 1 if you have struct addrinfo.]),,
709 #ifdef HAVE_WINDOWS_H
710 #ifndef WIN32_LEAN_AND_MEAN
711 #define WIN32_LEAN_AND_MEAN
714 #ifdef HAVE_WINSOCK2_H
715 #include <winsock2.h>
716 #ifdef HAVE_WS2TCPIP_H
717 #include <ws2tcpip.h>
721 #ifdef HAVE_SYS_TYPES_H
722 #include <sys/types.h>
724 #ifdef HAVE_NETINET_IN_H
725 #include <netinet/in.h>
727 #ifdef HAVE_SYS_SOCKET_H
728 #include <sys/socket.h>
738 AC_CHECK_FUNCS([bitncmp \
744 AC_MSG_CHECKING([deeper for $func])
752 eval "ac_cv_func_$func=yes"
753 AC_DEFINE_UNQUOTED([AS_TR_CPP([HAVE_$func])], [1],
754 [Define to 1 if you have the $func function.])
756 AC_MSG_RESULT([but still no])
761 dnl Check for inet_net_pton
762 AC_CHECK_FUNCS(inet_net_pton)
763 dnl Again, some systems have it, but not IPv6
764 if test "$ac_cv_func_inet_net_pton" = "yes" ; then
765 AC_MSG_CHECKING(if inet_net_pton supports IPv6)
768 #ifdef HAVE_SYS_TYPES_H
769 #include <sys/types.h>
771 #ifdef HAVE_SYS_SOCKET_H
772 #include <sys/socket.h>
774 #ifdef HAVE_NETINET_IN_H
775 #include <netinet/in.h>
779 struct in6_addr addr6;
780 if (inet_net_pton(AF_INET6, "::1", &addr6, sizeof(addr6)) < 1)
787 AC_DEFINE_UNQUOTED(HAVE_INET_NET_PTON_IPV6,1,[Define to 1 if inet_net_pton supports IPv6.])
788 ], AC_MSG_RESULT(no),AC_MSG_RESULT(no))
792 AC_CHECK_SIZEOF(struct in6_addr, ,
795 #ifdef HAVE_WINDOWS_H
796 #ifndef WIN32_LEAN_AND_MEAN
797 #define WIN32_LEAN_AND_MEAN
800 #ifdef HAVE_WINSOCK2_H
801 #include <winsock2.h>
802 #ifdef HAVE_WS2TCPIP_H
803 #include <ws2tcpip.h>
807 #ifdef HAVE_SYS_TYPES_H
808 #include <sys/types.h>
810 #ifdef HAVE_SYS_SOCKET_H
811 #include <sys/socket.h>
813 #ifdef HAVE_NETINET_IN_H
814 #include <netinet/in.h>
820 AC_CHECK_SIZEOF(struct in_addr, ,
823 #ifdef HAVE_WINDOWS_H
824 #ifndef WIN32_LEAN_AND_MEAN
825 #define WIN32_LEAN_AND_MEAN
828 #ifdef HAVE_WINSOCK2_H
829 #include <winsock2.h>
830 #ifdef HAVE_WS2TCPIP_H
831 #include <ws2tcpip.h>
835 #ifdef HAVE_SYS_TYPES_H
836 #include <sys/types.h>
838 #ifdef HAVE_SYS_SOCKET_H
839 #include <sys/socket.h>
841 #ifdef HAVE_NETINET_IN_H
842 #include <netinet/in.h>
849 dnl Check if the getnameinfo function is available
850 dnl and get the types of five of its arguments.
851 CURL_CHECK_FUNC_GETNAMEINFO
854 CURL_CHECK_NONBLOCKING_SOCKET
857 [AC_DEFINE(ARES_BIG_ENDIAN, 1,
858 [define this if ares is built for a big endian system])],
860 [AC_MSG_WARN([couldn't figure out endianess, assuming little endian!])]
863 dnl Check for user-specified random device
865 AC_HELP_STRING([--with-random=FILE],
866 [read randomness from FILE (default=/dev/urandom)]),
867 [ RANDOM_FILE="$withval" ],
869 dnl Check for random device. If we're cross compiling, we can't
870 dnl check, and it's better to assume it doesn't exist than it is
871 dnl to fail on AC_CHECK_FILE or later.
872 if test "$cross_compiling" = "no"; then
873 AC_CHECK_FILE("/dev/urandom", [ RANDOM_FILE="/dev/urandom"] )
875 AC_MSG_WARN([cannot check for /dev/urandom while cross compiling; assuming none])
880 if test -n "$RANDOM_FILE" && test X"$RANDOM_FILE" != Xno ; then
881 AC_SUBST(RANDOM_FILE)
882 AC_DEFINE_UNQUOTED(RANDOM_FILE, "$RANDOM_FILE",
883 [a suitable file/device to read random data from])
886 CARES_PRIVATE_LIBS="$LIBS"
887 AC_SUBST(CARES_PRIVATE_LIBS)
889 dnl squeeze whitespace out of some variables
897 squeeze CARES_PRIVATE_LIBS
899 AC_CONFIG_FILES([Makefile libcares.pc])