dnl configure.in for libevent dnl Copyright 2000-2007 Niels Provos dnl Copyright 2007-2012 Niels Provos and Nick Mathewson dnl dnl See LICENSE for copying information. dnl dnl Original version Dug Song AC_PREREQ(2.59c) AC_INIT(event.c) AC_CONFIG_MACRO_DIR([m4]) AM_INIT_AUTOMAKE(libevent,2.0.18-stable) dnl Enable silent Automake rules if present m4_ifdef([AM_SILENT_RULES],[AM_SILENT_RULES([yes])]) AM_CONFIG_HEADER(config.h) AC_DEFINE(NUMERIC_VERSION, 0x02001200, [Numeric representation of the version]) dnl Initialize prefix. if test "$prefix" = "NONE"; then prefix="/usr/local" fi AC_CANONICAL_BUILD AC_CANONICAL_HOST dnl the 'build' machine is where we run configure and compile dnl the 'host' machine is where the resulting stuff runs. case "$host_os" in osf5*) CFLAGS="$CFLAGS -D_OSF_SOURCE" ;; esac dnl Checks for programs. AC_PROG_CC AM_PROG_CC_C_O AC_PROG_INSTALL AC_PROG_LN_S AC_PROG_MKDIR_P AC_PROG_GCC_TRADITIONAL if test "$GCC" = "yes" ; then # Enable many gcc warnings by default... CFLAGS="$CFLAGS -Wall" # And disable the strict-aliasing optimization, since it breaks # our sockaddr-handling code in strange ways. CFLAGS="$CFLAGS -fno-strict-aliasing" fi # OS X Lion started deprecating the system openssl. Let's just disable # all deprecation warnings on OS X. case "$host_os" in darwin*) CFLAGS="$CFLAGS -Wno-deprecated-declarations" ;; esac AC_ARG_ENABLE(gcc-warnings, AS_HELP_STRING(--enable-gcc-warnings, enable verbose warnings with GCC)) AC_ARG_ENABLE(thread-support, AS_HELP_STRING(--disable-thread-support, disable support for threading), [], [enable_thread_support=yes]) AC_ARG_ENABLE(malloc-replacement, AS_HELP_STRING(--disable-malloc-replacement, disable support for replacing the memory mgt functions), [], [enable_malloc_replacement=yes]) AC_ARG_ENABLE(openssl, AS_HELP_STRING(--disable-openssl, disable support for openssl encryption), [], [enable_openssl=yes]) AC_ARG_ENABLE(debug-mode, AS_HELP_STRING(--disable-debug-mode, disable support for running in debug mode), [], [enable_debug_mode=yes]) AC_ARG_ENABLE([libevent-install], AS_HELP_STRING([--disable-libevent-install, disable installation of libevent]), [], [enable_libevent_install=yes]) AC_ARG_ENABLE([libevent-regress], AS_HELP_STRING([--disable-libevent-regress, skip regress in make check]), [], [enable_libevent_regress=yes]) AC_ARG_ENABLE([function-sections], AS_HELP_STRING([--enable-function-sections, make static library allow smaller binaries with --gc-sections]), [], [enable_function_sections=no]) AC_PROG_LIBTOOL dnl Uncomment "AC_DISABLE_SHARED" to make shared librraries not get dnl built by default. You can also turn shared libs on and off from dnl the command line with --enable-shared and --disable-shared. dnl AC_DISABLE_SHARED AC_SUBST(LIBTOOL_DEPS) AM_CONDITIONAL([BUILD_REGRESS], [test "$enable_libevent_regress" = "yes"]) dnl Checks for libraries. AC_SEARCH_LIBS([inet_ntoa], [nsl]) AC_SEARCH_LIBS([socket], [socket]) AC_SEARCH_LIBS([inet_aton], [resolv]) AC_SEARCH_LIBS([clock_gettime], [rt]) AC_SEARCH_LIBS([sendfile], [sendfile]) dnl - check if the macro WIN32 is defined on this compiler. dnl - (this is how we check for a windows version of GCC) AC_MSG_CHECKING(for WIN32) AC_TRY_COMPILE(, [ #ifndef WIN32 die horribly #endif ], bwin32=true; AC_MSG_RESULT(yes), bwin32=false; AC_MSG_RESULT(no), ) dnl - check if the macro __CYGWIN__ is defined on this compiler. dnl - (this is how we check for a cygwin version of GCC) AC_MSG_CHECKING(for CYGWIN) AC_TRY_COMPILE(, [ #ifndef __CYGWIN__ die horribly #endif ], cygwin=true; AC_MSG_RESULT(yes), cygwin=false; AC_MSG_RESULT(no), ) AC_CHECK_HEADERS([zlib.h]) if test "x$ac_cv_header_zlib_h" = "xyes"; then dnl Determine if we have zlib for regression tests dnl Don't put this one in LIBS save_LIBS="$LIBS" LIBS="" ZLIB_LIBS="" have_zlib=no AC_SEARCH_LIBS([inflateEnd], [z], [have_zlib=yes ZLIB_LIBS="$LIBS" AC_DEFINE(HAVE_LIBZ, 1, [Define if the system has zlib])]) LIBS="$save_LIBS" AC_SUBST(ZLIB_LIBS) fi AM_CONDITIONAL(ZLIB_REGRESS, [test "$have_zlib" = "yes"]) dnl See if we have openssl. This doesn't go in LIBS either. if test "$bwin32" = true; then EV_LIB_WS32=-lws2_32 EV_LIB_GDI=-lgdi32 else EV_LIB_WS32= EV_LIB_GDI= fi AC_SUBST(EV_LIB_WS32) AC_SUBST(EV_LIB_GDI) AC_SUBST(OPENSSL_LIBADD) AC_CHECK_HEADERS([openssl/bio.h]) if test "$enable_openssl" = "yes"; then save_LIBS="$LIBS" LIBS="" OPENSSL_LIBS="" have_openssl=no AC_SEARCH_LIBS([SSL_new], [ssl], [have_openssl=yes OPENSSL_LIBS="$LIBS -lcrypto $EV_LIB_GDI $EV_LIB_WS32 $OPENSSL_LIBADD" AC_DEFINE(HAVE_OPENSSL, 1, [Define if the system has openssl])], [have_openssl=no], [-lcrypto $EV_LIB_GDI $EV_LIB_WS32 $OPENSSL_LIBADD]) LIBS="$save_LIBS" AC_SUBST(OPENSSL_LIBS) fi dnl Checks for header files. AC_HEADER_STDC AC_CHECK_HEADERS([fcntl.h stdarg.h inttypes.h stdint.h stddef.h poll.h unistd.h sys/epoll.h sys/time.h sys/queue.h sys/event.h sys/param.h sys/ioctl.h sys/select.h sys/devpoll.h port.h netinet/in.h netinet/in6.h sys/socket.h sys/uio.h arpa/inet.h sys/eventfd.h sys/mman.h sys/sendfile.h sys/wait.h netdb.h]) AC_CHECK_HEADERS(sys/sysctl.h, [], [], [ #ifdef HAVE_SYS_PARAM_H #include #endif ]) if test "x$ac_cv_header_sys_queue_h" = "xyes"; then AC_MSG_CHECKING(for TAILQ_FOREACH in sys/queue.h) AC_EGREP_CPP(yes, [ #include #ifdef TAILQ_FOREACH yes #endif ], [AC_MSG_RESULT(yes) AC_DEFINE(HAVE_TAILQFOREACH, 1, [Define if TAILQ_FOREACH is defined in ])], AC_MSG_RESULT(no) ) fi if test "x$ac_cv_header_sys_time_h" = "xyes"; then AC_MSG_CHECKING(for timeradd in sys/time.h) AC_EGREP_CPP(yes, [ #include #ifdef timeradd yes #endif ], [ AC_DEFINE(HAVE_TIMERADD, 1, [Define if timeradd is defined in ]) AC_MSG_RESULT(yes)] ,AC_MSG_RESULT(no) ) fi if test "x$ac_cv_header_sys_time_h" = "xyes"; then AC_MSG_CHECKING(for timercmp in sys/time.h) AC_EGREP_CPP(yes, [ #include #ifdef timercmp yes #endif ], [ AC_DEFINE(HAVE_TIMERCMP, 1, [Define if timercmp is defined in ]) AC_MSG_RESULT(yes)] ,AC_MSG_RESULT(no) ) fi if test "x$ac_cv_header_sys_time_h" = "xyes"; then AC_MSG_CHECKING(for timerclear in sys/time.h) AC_EGREP_CPP(yes, [ #include #ifdef timerclear yes #endif ], [ AC_DEFINE(HAVE_TIMERCLEAR, 1, [Define if timerclear is defined in ]) AC_MSG_RESULT(yes)] ,AC_MSG_RESULT(no) ) fi if test "x$ac_cv_header_sys_time_h" = "xyes"; then AC_MSG_CHECKING(for timerisset in sys/time.h) AC_EGREP_CPP(yes, [ #include #ifdef timerisset yes #endif ], [ AC_DEFINE(HAVE_TIMERISSET, 1, [Define if timerisset is defined in ]) AC_MSG_RESULT(yes)] ,AC_MSG_RESULT(no) ) fi if test "x$ac_cv_header_sys_sysctl_h" = "xyes"; then AC_CHECK_DECLS([CTL_KERN, KERN_RANDOM, RANDOM_UUID, KERN_ARND], [], [], [[#include #include ]] ) fi AM_CONDITIONAL(BUILD_WIN32, test x$bwin32 = xtrue) AM_CONDITIONAL(BUILD_CYGWIN, test x$cygwin = xtrue) AM_CONDITIONAL(BUILD_WITH_NO_UNDEFINED, test x$bwin32 = xtrue || test x$cygwin = xtrue) if test x$bwin32 = xtrue; then AC_SEARCH_LIBS([getservbyname],[ws2_32]) fi dnl Checks for typedefs, structures, and compiler characteristics. AC_C_CONST AC_C_INLINE AC_HEADER_TIME dnl Checks for library functions. AC_CHECK_FUNCS([gettimeofday vasprintf fcntl clock_gettime strtok_r strsep]) AC_CHECK_FUNCS([getnameinfo strlcpy inet_ntop inet_pton signal sigaction strtoll inet_aton pipe eventfd sendfile mmap splice arc4random arc4random_buf issetugid geteuid getegid getprotobynumber setenv unsetenv putenv sysctl]) AC_CACHE_CHECK( [for getaddrinfo], [libevent_cv_getaddrinfo], [AC_LINK_IFELSE( [AC_LANG_PROGRAM( [[ #ifdef HAVE_NETDB_H #include #endif ]], [[ getaddrinfo; ]] )], [libevent_cv_getaddrinfo=yes], [libevent_cv_getaddrinfo=no] )] ) if test "$libevent_cv_getaddrinfo" = "yes" ; then AC_DEFINE([HAVE_GETADDRINFO], [1], [Do we have getaddrinfo()?]) else AC_CHECK_FUNCS([getservbyname]) # Check for gethostbyname_r in all its glorious incompatible versions. # (This is cut-and-pasted from Tor, which based its logic on # Python's configure.in.) AH_TEMPLATE(HAVE_GETHOSTBYNAME_R, [Define this if you have any gethostbyname_r()]) AC_CHECK_FUNC(gethostbyname_r, [ AC_MSG_CHECKING([how many arguments gethostbyname_r() wants]) OLD_CFLAGS=$CFLAGS CFLAGS="$CFLAGS $MY_CPPFLAGS $MY_THREAD_CPPFLAGS $MY_CFLAGS" AC_COMPILE_IFELSE([AC_LANG_PROGRAM([ #include ], [[ char *cp1, *cp2; struct hostent *h1, *h2; int i1, i2; (void)gethostbyname_r(cp1,h1,cp2,i1,&h2,&i2); ]])],[ AC_DEFINE(HAVE_GETHOSTBYNAME_R) AC_DEFINE(HAVE_GETHOSTBYNAME_R_6_ARG, 1, [Define this if gethostbyname_r takes 6 arguments]) AC_MSG_RESULT(6) ], [ AC_TRY_COMPILE([ #include ], [ char *cp1, *cp2; struct hostent *h1; int i1, i2; (void)gethostbyname_r(cp1,h1,cp2,i1,&i2); ], [ AC_DEFINE(HAVE_GETHOSTBYNAME_R) AC_DEFINE(HAVE_GETHOSTBYNAME_R_5_ARG, 1, [Define this if gethostbyname_r takes 5 arguments]) AC_MSG_RESULT(5) ], [ AC_TRY_COMPILE([ #include ], [ char *cp1; struct hostent *h1; struct hostent_data hd; (void) gethostbyname_r(cp1,h1,&hd); ], [ AC_DEFINE(HAVE_GETHOSTBYNAME_R) AC_DEFINE(HAVE_GETHOSTBYNAME_R_3_ARG, 1, [Define this if gethostbyname_r takes 3 arguments]) AC_MSG_RESULT(3) ], [ AC_MSG_RESULT(0) ]) ]) ]) CFLAGS=$OLD_CFLAGS ]) fi AC_CHECK_SIZEOF(long) AC_MSG_CHECKING(for F_SETFD in fcntl.h) AC_EGREP_CPP(yes, [ #define _GNU_SOURCE #include #ifdef F_SETFD yes #endif ], [ AC_DEFINE(HAVE_SETFD, 1, [Define if F_SETFD is defined in ]) AC_MSG_RESULT(yes) ], AC_MSG_RESULT(no)) needsignal=no haveselect=no if test x$bwin32 != xtrue; then AC_CHECK_FUNCS(select, [haveselect=yes], ) if test "x$haveselect" = "xyes" ; then needsignal=yes fi fi AM_CONDITIONAL(SELECT_BACKEND, [test "x$haveselect" = "xyes"]) havepoll=no AC_CHECK_FUNCS(poll, [havepoll=yes], ) if test "x$havepoll" = "xyes" ; then needsignal=yes fi AM_CONDITIONAL(POLL_BACKEND, [test "x$havepoll" = "xyes"]) havedevpoll=no if test "x$ac_cv_header_sys_devpoll_h" = "xyes"; then AC_DEFINE(HAVE_DEVPOLL, 1, [Define if /dev/poll is available]) fi AM_CONDITIONAL(DEVPOLL_BACKEND, [test "x$ac_cv_header_sys_devpoll_h" = "xyes"]) havekqueue=no if test "x$ac_cv_header_sys_event_h" = "xyes"; then AC_CHECK_FUNCS(kqueue, [havekqueue=yes], ) if test "x$havekqueue" = "xyes" ; then AC_MSG_CHECKING(for working kqueue) AC_TRY_RUN( #include #include #include #include #include #include int main(int argc, char **argv) { int kq; int n; int fd[[2]]; struct kevent ev; struct timespec ts; char buf[[8000]]; if (pipe(fd) == -1) exit(1); if (fcntl(fd[[1]], F_SETFL, O_NONBLOCK) == -1) exit(1); while ((n = write(fd[[1]], buf, sizeof(buf))) == sizeof(buf)) ; if ((kq = kqueue()) == -1) exit(1); memset(&ev, 0, sizeof(ev)); ev.ident = fd[[1]]; ev.filter = EVFILT_WRITE; ev.flags = EV_ADD | EV_ENABLE; n = kevent(kq, &ev, 1, NULL, 0, NULL); if (n == -1) exit(1); read(fd[[0]], buf, sizeof(buf)); ts.tv_sec = 0; ts.tv_nsec = 0; n = kevent(kq, NULL, 0, &ev, 1, &ts); if (n == -1 || n == 0) exit(1); exit(0); }, [AC_MSG_RESULT(yes) AC_DEFINE(HAVE_WORKING_KQUEUE, 1, [Define if kqueue works correctly with pipes]) havekqueue=yes ], AC_MSG_RESULT(no), AC_MSG_RESULT(no)) fi fi AM_CONDITIONAL(KQUEUE_BACKEND, [test "x$havekqueue" = "xyes"]) haveepollsyscall=no haveepoll=no AC_CHECK_FUNCS(epoll_ctl, [haveepoll=yes], ) if test "x$haveepoll" = "xyes" ; then AC_DEFINE(HAVE_EPOLL, 1, [Define if your system supports the epoll system calls]) needsignal=yes fi if test "x$ac_cv_header_sys_epoll_h" = "xyes"; then if test "x$haveepoll" = "xno" ; then AC_MSG_CHECKING(for epoll system call) AC_TRY_RUN( #include #include #include #include #include #include int epoll_create(int size) { return (syscall(__NR_epoll_create, size)); } int main(int argc, char **argv) { int epfd; epfd = epoll_create(256); exit (epfd == -1 ? 1 : 0); }, [AC_MSG_RESULT(yes) AC_DEFINE(HAVE_EPOLL, 1, [Define if your system supports the epoll system calls]) needsignal=yes have_epoll=yes AC_LIBOBJ(epoll_sub) ], AC_MSG_RESULT(no), AC_MSG_RESULT(no)) fi fi AM_CONDITIONAL(EPOLL_BACKEND, [test "x$haveepoll" = "xyes"]) haveeventports=no AC_CHECK_FUNCS(port_create, [haveeventports=yes], ) if test "x$haveeventports" = "xyes" ; then AC_DEFINE(HAVE_EVENT_PORTS, 1, [Define if your system supports event ports]) needsignal=yes fi AM_CONDITIONAL(EVPORT_BACKEND, [test "x$haveeventports" = "xyes"]) if test "x$bwin32" = "xtrue"; then needsignal=yes fi AM_CONDITIONAL(SIGNAL_SUPPORT, [test "x$needsignal" = "xyes"]) AC_TYPE_PID_T AC_TYPE_SIZE_T AC_TYPE_SSIZE_T AC_CHECK_TYPES([uint64_t, uint32_t, uint16_t, uint8_t, uintptr_t], , , [#ifdef HAVE_STDINT_H #include #elif defined(HAVE_INTTYPES_H) #include #endif #ifdef HAVE_SYS_TYPES_H #include #endif]) AC_CHECK_TYPES([fd_mask], , , [#ifdef HAVE_SYS_TYPES_H #include #endif #ifdef HAVE_SYS_SELECT_H #include #endif]) AC_CHECK_SIZEOF(long long) AC_CHECK_SIZEOF(long) AC_CHECK_SIZEOF(int) AC_CHECK_SIZEOF(short) AC_CHECK_SIZEOF(size_t) AC_CHECK_SIZEOF(void *) AC_CHECK_TYPES([struct in6_addr, struct sockaddr_in6, sa_family_t, struct addrinfo, struct sockaddr_storage], , , [#define _GNU_SOURCE #include #ifdef HAVE_NETINET_IN_H #include #endif #ifdef HAVE_NETINET_IN6_H #include #endif #ifdef HAVE_SYS_SOCKET_H #include #endif #ifdef HAVE_NETDB_H #include #endif #ifdef WIN32 #define WIN32_WINNT 0x400 #define _WIN32_WINNT 0x400 #define WIN32_LEAN_AND_MEAN #if defined(_MSC_VER) && (_MSC_VER < 1300) #include #else #include #include #endif #endif ]) AC_CHECK_MEMBERS([struct in6_addr.s6_addr32, struct in6_addr.s6_addr16, struct sockaddr_in.sin_len, struct sockaddr_in6.sin6_len, struct sockaddr_storage.ss_family, struct sockaddr_storage.__ss_family], , , [#include #ifdef HAVE_NETINET_IN_H #include #endif #ifdef HAVE_NETINET_IN6_H #include #endif #ifdef HAVE_SYS_SOCKET_H #include #endif #ifdef WIN32 #define WIN32_WINNT 0x400 #define _WIN32_WINNT 0x400 #define WIN32_LEAN_AND_MEAN #if defined(_MSC_VER) && (_MSC_VER < 1300) #include #else #include #include #endif #endif ]) AC_MSG_CHECKING([for socklen_t]) AC_TRY_COMPILE([ #include #include ], [socklen_t x;], AC_MSG_RESULT([yes]), [AC_MSG_RESULT([no]) AC_DEFINE(socklen_t, unsigned int, [Define to unsigned int if you dont have it])] ) AC_MSG_CHECKING([whether our compiler supports __func__]) AC_TRY_COMPILE([], [ const char *cp = __func__; ], AC_MSG_RESULT([yes]), AC_MSG_RESULT([no]) AC_MSG_CHECKING([whether our compiler supports __FUNCTION__]) AC_TRY_COMPILE([], [ const char *cp = __FUNCTION__; ], AC_MSG_RESULT([yes]) AC_DEFINE(__func__, __FUNCTION__, [Define to appropriate substitue if compiler doesnt have __func__]), AC_MSG_RESULT([no]) AC_DEFINE(__func__, __FILE__, [Define to appropriate substitue if compiler doesnt have __func__]))) # check if we can compile with pthreads have_pthreads=no if test x$bwin32 != xtrue && test "$enable_thread_support" != "no"; then ACX_PTHREAD([ AC_DEFINE(HAVE_PTHREADS, 1, [Define if we have pthreads on this system]) have_pthreads=yes]) CFLAGS="$CFLAGS $PTHREAD_CFLAGS" AC_CHECK_SIZEOF(pthread_t, , [AC_INCLUDES_DEFAULT() #include ] ) fi AM_CONDITIONAL(PTHREADS, [test "$have_pthreads" != "no" && test "$enable_thread_support" != "no"]) # check if we should compile locking into the library if test x$enable_thread_support = xno; then AC_DEFINE(DISABLE_THREAD_SUPPORT, 1, [Define if libevent should not be compiled with thread support]) fi # check if we should hard-code the mm functions. if test x$enable_malloc_replacement = xno; then AC_DEFINE(DISABLE_MM_REPLACEMENT, 1, [Define if libevent should not allow replacing the mm functions]) fi # check if we should hard-code debugging out if test x$enable_debug_mode = xno; then AC_DEFINE(DISABLE_DEBUG_MODE, 1, [Define if libevent should build without support for a debug mode]) fi # check if we have and should use openssl AM_CONDITIONAL(OPENSSL, [test "$enable_openssl" != "no" && test "$have_openssl" = "yes"]) # Add some more warnings which we use in development but not in the # released versions. (Some relevant gcc versions can't handle these.) if test x$enable_gcc_warnings = xyes && test "$GCC" = "yes"; then AC_COMPILE_IFELSE([AC_LANG_PROGRAM([], [ #if !defined(__GNUC__) || (__GNUC__ < 4) #error #endif])], have_gcc4=yes, have_gcc4=no) AC_COMPILE_IFELSE([AC_LANG_PROGRAM([], [ #if !defined(__GNUC__) || (__GNUC__ < 4) || (__GNUC__ == 4 && __GNUC_MINOR__ < 2) #error #endif])], have_gcc42=yes, have_gcc42=no) AC_COMPILE_IFELSE([AC_LANG_PROGRAM([], [ #if !defined(__GNUC__) || (__GNUC__ < 4) || (__GNUC__ == 4 && __GNUC_MINOR__ < 5) #error #endif])], have_gcc45=yes, have_gcc45=no) AC_COMPILE_IFELSE([AC_LANG_PROGRAM([], [ #if !defined(__clang__) #error #endif])], have_clang=yes, have_clang=no) CFLAGS="$CFLAGS -W -Wfloat-equal -Wundef -Wpointer-arith -Wstrict-prototypes -Wmissing-prototypes -Wwrite-strings -Wredundant-decls -Wchar-subscripts -Wcomment -Wformat -Wwrite-strings -Wmissing-declarations -Wredundant-decls -Wnested-externs -Wbad-function-cast -Wswitch-enum -Werror" CFLAGS="$CFLAGS -Wno-unused-parameter -Wstrict-aliasing" if test x$have_gcc4 = xyes ; then # These warnings break gcc 3.3.5 and work on gcc 4.0.2 CFLAGS="$CFLAGS -Winit-self -Wmissing-field-initializers -Wdeclaration-after-statement" #CFLAGS="$CFLAGS -Wold-style-definition" fi if test x$have_gcc42 = xyes ; then # These warnings break gcc 4.0.2 and work on gcc 4.2 CFLAGS="$CFLAGS -Waddress" fi if test x$have_gcc42 = xyes && test x$have_clang = xno; then # These warnings break gcc 4.0.2 and clang, but work on gcc 4.2 CFLAGS="$CFLAGS -Wnormalized=id -Woverride-init" fi if test x$have_gcc45 = xyes ; then # These warnings work on gcc 4.5 CFLAGS="$CFLAGS -Wlogical-op" fi if test x$have_clang = xyes; then # Disable the unused-function warnings, because these trigger # for minheap-internal.h related code. CFLAGS="$CFLAGS -Wno-unused-function" fi ##This will break the world on some 64-bit architectures # CFLAGS="$CFLAGS -Winline" fi LIBEVENT_GC_SECTIONS= if test "$GCC" = yes && test "$enable_function_sections" = yes ; then AC_CACHE_CHECK( [if linker supports omitting unused code and data], [libevent_cv_gc_sections_runs], [ dnl NetBSD will link but likely not run with --gc-sections dnl http://bugs.ntp.org/1844 dnl http://gnats.netbsd.org/40401 dnl --gc-sections causes attempt to load as linux elf, with dnl wrong syscalls in place. Test a little gauntlet of dnl simple stdio read code checking for errors, expecting dnl enough syscall differences that the NetBSD code will dnl fail even with Linux emulation working as designed. dnl A shorter test could be refined by someone with access dnl to a NetBSD host with Linux emulation working. origCFLAGS="$CFLAGS" CFLAGS="$CFLAGS -Wl,--gc-sections" AC_LINK_IFELSE( [AC_LANG_PROGRAM( [[ #include #include ]], [[ FILE * fpC; char buf[32]; size_t cch; int read_success_once; fpC = fopen("conftest.c", "r"); if (NULL == fpC) exit(1); do { cch = fread(buf, sizeof(buf), 1, fpC); read_success_once |= (0 != cch); } while (0 != cch); if (!read_success_once) exit(2); if (!feof(fpC)) exit(3); if (0 != fclose(fpC)) exit(4); exit(EXIT_SUCCESS); ]] )], [ dnl We have to do this invocation manually so that we can dnl get the output of conftest.err to make sure it doesn't dnl mention gc-sections. if test "X$cross_compiling" = "Xyes" || grep gc-sections conftest.err ; then libevent_cv_gc_sections_runs=no else libevent_cv_gc_sections_runs=no ./conftest >/dev/null 2>&1 && libevent_cv_gc_sections_runs=yes fi ], [libevent_cv_gc_sections_runs=no] ) CFLAGS="$origCFLAGS" AS_UNSET([origCFLAGS]) ] ) case "$libevent_cv_gc_sections_runs" in yes) CFLAGS="-ffunction-sections -fdata-sections $CFLAGS" LIBEVENT_GC_SECTIONS="-Wl,--gc-sections" ;; esac fi AC_SUBST([LIBEVENT_GC_SECTIONS]) AM_CONDITIONAL([INSTALL_LIBEVENT], [test "$enable_libevent_install" = "yes"]) AC_CONFIG_FILES( [libevent.pc libevent_openssl.pc libevent_pthreads.pc] ) AC_OUTPUT(Makefile include/Makefile test/Makefile sample/Makefile)