# mmap(2) blacklisting. Some platforms provide the mmap library routine # but don't support all of the features we need from it. AC_DEFUN([AC_FUNC_MMAP_BLACKLIST], [ AC_CHECK_HEADER([sys/mman.h], [libffi_header_sys_mman_h=yes], [libffi_header_sys_mman_h=no]) AC_CHECK_FUNC([mmap], [libffi_func_mmap=yes], [libffi_func_mmap=no]) if test "$libffi_header_sys_mman_h" != yes \ || test "$libffi_func_mmap" != yes; then ac_cv_func_mmap_file=no ac_cv_func_mmap_dev_zero=no ac_cv_func_mmap_anon=no else AC_CACHE_CHECK([whether read-only mmap of a plain file works], ac_cv_func_mmap_file, [# Add a system to this blacklist if # mmap(0, stat_size, PROT_READ, MAP_PRIVATE, fd, 0) doesn't return a # memory area containing the same data that you'd get if you applied # read() to the same fd. The only system known to have a problem here # is VMS, where text files have record structure. case "$host_os" in vms* | ultrix*) ac_cv_func_mmap_file=no ;; *) ac_cv_func_mmap_file=yes;; esac]) AC_CACHE_CHECK([whether mmap from /dev/zero works], ac_cv_func_mmap_dev_zero, [# Add a system to this blacklist if it has mmap() but /dev/zero # does not exist, or if mmapping /dev/zero does not give anonymous # zeroed pages with both the following properties: # 1. If you map N consecutive pages in with one call, and then # unmap any subset of those pages, the pages that were not # explicitly unmapped remain accessible. # 2. If you map two adjacent blocks of memory and then unmap them # both at once, they must both go away. # Systems known to be in this category are Windows (all variants), # VMS, and Darwin. case "$host_os" in vms* | cygwin* | pe | mingw* | darwin* | ultrix* | hpux10* | hpux11.00) ac_cv_func_mmap_dev_zero=no ;; *) ac_cv_func_mmap_dev_zero=yes;; esac]) # Unlike /dev/zero, the MAP_ANON(YMOUS) defines can be probed for. AC_CACHE_CHECK([for MAP_ANON(YMOUS)], ac_cv_decl_map_anon, [AC_TRY_COMPILE( [#include #include #include #ifndef MAP_ANONYMOUS #define MAP_ANONYMOUS MAP_ANON #endif ], [int n = MAP_ANONYMOUS;], ac_cv_decl_map_anon=yes, ac_cv_decl_map_anon=no)]) if test $ac_cv_decl_map_anon = no; then ac_cv_func_mmap_anon=no else AC_CACHE_CHECK([whether mmap with MAP_ANON(YMOUS) works], ac_cv_func_mmap_anon, [# Add a system to this blacklist if it has mmap() and MAP_ANON or # MAP_ANONYMOUS, but using mmap(..., MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) # doesn't give anonymous zeroed pages with the same properties listed # above for use of /dev/zero. # Systems known to be in this category are Windows, VMS, and SCO Unix. case "$host_os" in vms* | cygwin* | pe | mingw* | sco* | udk* ) ac_cv_func_mmap_anon=no ;; *) ac_cv_func_mmap_anon=yes;; esac]) fi fi if test $ac_cv_func_mmap_file = yes; then AC_DEFINE(HAVE_MMAP_FILE, 1, [Define if read-only mmap of a plain file works.]) fi if test $ac_cv_func_mmap_dev_zero = yes; then AC_DEFINE(HAVE_MMAP_DEV_ZERO, 1, [Define if mmap of /dev/zero works.]) fi if test $ac_cv_func_mmap_anon = yes; then AC_DEFINE(HAVE_MMAP_ANON, 1, [Define if mmap with MAP_ANON(YMOUS) works.]) fi ]) dnl ---------------------------------------------------------------------- dnl This whole bit snagged from libstdc++-v3, via libatomic. dnl dnl LIBAT_ENABLE dnl (FEATURE, DEFAULT, HELP-ARG, HELP-STRING) dnl (FEATURE, DEFAULT, HELP-ARG, HELP-STRING, permit a|b|c) dnl (FEATURE, DEFAULT, HELP-ARG, HELP-STRING, SHELL-CODE-HANDLER) dnl dnl See docs/html/17_intro/configury.html#enable for documentation. dnl m4_define([LIBAT_ENABLE],[dnl m4_define([_g_switch],[--enable-$1])dnl m4_define([_g_help],[AC_HELP_STRING(_g_switch$3,[$4 @<:@default=$2@:>@])])dnl AC_ARG_ENABLE($1,_g_help, m4_bmatch([$5], [^permit ], [[ case "$enableval" in m4_bpatsubst([$5],[permit ])) ;; *) AC_MSG_ERROR(Unknown argument to enable/disable $1) ;; dnl Idea for future: generate a URL pointing to dnl "onlinedocs/configopts.html#whatever" esac ]], [^$], [[ case "$enableval" in yes|no) ;; *) AC_MSG_ERROR(Argument to enable/disable $1 must be yes or no) ;; esac ]], [[$5]]), [enable_]m4_bpatsubst([$1],-,_)[=][$2]) m4_undefine([_g_switch])dnl m4_undefine([_g_help])dnl ]) dnl dnl If GNU ld is in use, check to see if tricky linker opts can be used. If dnl the native linker is in use, all variables will be defined to something dnl safe (like an empty string). dnl dnl Defines: dnl SECTION_LDFLAGS='-Wl,--gc-sections' if possible dnl OPT_LDFLAGS='-Wl,-O1' if possible dnl LD (as a side effect of testing) dnl Sets: dnl with_gnu_ld dnl libat_ld_is_gold (possibly) dnl libat_gnu_ld_version (possibly) dnl dnl The last will be a single integer, e.g., version 1.23.45.0.67.89 will dnl set libat_gnu_ld_version to 12345. Zeros cause problems. dnl AC_DEFUN([LIBAT_CHECK_LINKER_FEATURES], [ # If we're not using GNU ld, then there's no point in even trying these # tests. Check for that first. We should have already tested for gld # by now (in libtool), but require it now just to be safe... test -z "$SECTION_LDFLAGS" && SECTION_LDFLAGS='' test -z "$OPT_LDFLAGS" && OPT_LDFLAGS='' AC_REQUIRE([AC_PROG_LD]) AC_REQUIRE([AC_PROG_AWK]) # The name set by libtool depends on the version of libtool. Shame on us # for depending on an impl detail, but c'est la vie. Older versions used # ac_cv_prog_gnu_ld, but now it's lt_cv_prog_gnu_ld, and is copied back on # top of with_gnu_ld (which is also set by --with-gnu-ld, so that actually # makes sense). We'll test with_gnu_ld everywhere else, so if that isn't # set (hence we're using an older libtool), then set it. if test x${with_gnu_ld+set} != xset; then if test x${ac_cv_prog_gnu_ld+set} != xset; then # We got through "ac_require(ac_prog_ld)" and still not set? Huh? with_gnu_ld=no else with_gnu_ld=$ac_cv_prog_gnu_ld fi fi # Start by getting the version number. I think the libtool test already # does some of this, but throws away the result. libat_ld_is_gold=no if $LD --version 2>/dev/null | grep 'GNU gold'> /dev/null 2>&1; then libat_ld_is_gold=yes fi changequote(,) ldver=`$LD --version 2>/dev/null | sed -e 's/[. ][0-9]\{8\}$//;s/.* \([^ ]\{1,\}\)$/\1/; q'` changequote([,]) libat_gnu_ld_version=`echo $ldver | \ $AWK -F. '{ if (NF<3) [$]3=0; print ([$]1*100+[$]2)*100+[$]3 }'` # Set --gc-sections. if test "$with_gnu_ld" = "notbroken"; then # GNU ld it is! Joy and bunny rabbits! # All these tests are for C++; save the language and the compiler flags. # Need to do this so that g++ won't try to link in libstdc++ ac_test_CFLAGS="${CFLAGS+set}" ac_save_CFLAGS="$CFLAGS" CFLAGS='-x c++ -Wl,--gc-sections' # Check for -Wl,--gc-sections # XXX This test is broken at the moment, as symbols required for linking # are now in libsupc++ (not built yet). In addition, this test has # cored on solaris in the past. In addition, --gc-sections doesn't # really work at the moment (keeps on discarding used sections, first # .eh_frame and now some of the glibc sections for iconv). # Bzzzzt. Thanks for playing, maybe next time. AC_MSG_CHECKING([for ld that supports -Wl,--gc-sections]) AC_TRY_RUN([ int main(void) { try { throw 1; } catch (...) { }; return 0; } ], [ac_sectionLDflags=yes],[ac_sectionLDflags=no], [ac_sectionLDflags=yes]) if test "$ac_test_CFLAGS" = set; then CFLAGS="$ac_save_CFLAGS" else # this is the suspicious part CFLAGS='' fi if test "$ac_sectionLDflags" = "yes"; then SECTION_LDFLAGS="-Wl,--gc-sections $SECTION_LDFLAGS" fi AC_MSG_RESULT($ac_sectionLDflags) fi # Set linker optimization flags. if test x"$with_gnu_ld" = x"yes"; then OPT_LDFLAGS="-Wl,-O1 $OPT_LDFLAGS" fi AC_SUBST(SECTION_LDFLAGS) AC_SUBST(OPT_LDFLAGS) ]) dnl dnl If GNU ld is in use, check to see if tricky linker opts can be used. If dnl the native linker is in use, all variables will be defined to something dnl safe (like an empty string). dnl dnl Defines: dnl SECTION_LDFLAGS='-Wl,--gc-sections' if possible dnl OPT_LDFLAGS='-Wl,-O1' if possible dnl LD (as a side effect of testing) dnl Sets: dnl with_gnu_ld dnl libat_ld_is_gold (possibly) dnl libat_gnu_ld_version (possibly) dnl dnl The last will be a single integer, e.g., version 1.23.45.0.67.89 will dnl set libat_gnu_ld_version to 12345. Zeros cause problems. dnl AC_DEFUN([LIBAT_CHECK_LINKER_FEATURES], [ # If we're not using GNU ld, then there's no point in even trying these # tests. Check for that first. We should have already tested for gld # by now (in libtool), but require it now just to be safe... test -z "$SECTION_LDFLAGS" && SECTION_LDFLAGS='' test -z "$OPT_LDFLAGS" && OPT_LDFLAGS='' AC_REQUIRE([AC_PROG_LD]) AC_REQUIRE([AC_PROG_AWK]) # The name set by libtool depends on the version of libtool. Shame on us # for depending on an impl detail, but c'est la vie. Older versions used # ac_cv_prog_gnu_ld, but now it's lt_cv_prog_gnu_ld, and is copied back on # top of with_gnu_ld (which is also set by --with-gnu-ld, so that actually # makes sense). We'll test with_gnu_ld everywhere else, so if that isn't # set (hence we're using an older libtool), then set it. if test x${with_gnu_ld+set} != xset; then if test x${ac_cv_prog_gnu_ld+set} != xset; then # We got through "ac_require(ac_prog_ld)" and still not set? Huh? with_gnu_ld=no else with_gnu_ld=$ac_cv_prog_gnu_ld fi fi # Start by getting the version number. I think the libtool test already # does some of this, but throws away the result. libat_ld_is_gold=no if $LD --version 2>/dev/null | grep 'GNU gold'> /dev/null 2>&1; then libat_ld_is_gold=yes fi changequote(,) ldver=`$LD --version 2>/dev/null | sed -e 's/[. ][0-9]\{8\}$//;s/.* \([^ ]\{1,\}\)$/\1/; q'` changequote([,]) libat_gnu_ld_version=`echo $ldver | \ $AWK -F. '{ if (NF<3) [$]3=0; print ([$]1*100+[$]2)*100+[$]3 }'` # Set --gc-sections. if test "$with_gnu_ld" = "notbroken"; then # GNU ld it is! Joy and bunny rabbits! # All these tests are for C++; save the language and the compiler flags. # Need to do this so that g++ won't try to link in libstdc++ ac_test_CFLAGS="${CFLAGS+set}" ac_save_CFLAGS="$CFLAGS" CFLAGS='-x c++ -Wl,--gc-sections' # Check for -Wl,--gc-sections # XXX This test is broken at the moment, as symbols required for linking # are now in libsupc++ (not built yet). In addition, this test has # cored on solaris in the past. In addition, --gc-sections doesn't # really work at the moment (keeps on discarding used sections, first # .eh_frame and now some of the glibc sections for iconv). # Bzzzzt. Thanks for playing, maybe next time. AC_MSG_CHECKING([for ld that supports -Wl,--gc-sections]) AC_TRY_RUN([ int main(void) { try { throw 1; } catch (...) { }; return 0; } ], [ac_sectionLDflags=yes],[ac_sectionLDflags=no], [ac_sectionLDflags=yes]) if test "$ac_test_CFLAGS" = set; then CFLAGS="$ac_save_CFLAGS" else # this is the suspicious part CFLAGS='' fi if test "$ac_sectionLDflags" = "yes"; then SECTION_LDFLAGS="-Wl,--gc-sections $SECTION_LDFLAGS" fi AC_MSG_RESULT($ac_sectionLDflags) fi # Set linker optimization flags. if test x"$with_gnu_ld" = x"yes"; then OPT_LDFLAGS="-Wl,-O1 $OPT_LDFLAGS" fi AC_SUBST(SECTION_LDFLAGS) AC_SUBST(OPT_LDFLAGS) ]) dnl dnl Add version tags to symbols in shared library (or not), additionally dnl marking other symbols as private/local (or not). dnl dnl --enable-symvers=style adds a version script to the linker call when dnl creating the shared library. The choice of version script is dnl controlled by 'style'. dnl --disable-symvers does not. dnl + Usage: LIBAT_ENABLE_SYMVERS[(DEFAULT)] dnl Where DEFAULT is either 'yes' or 'no'. Passing `yes' tries to dnl choose a default style based on linker characteristics. Passing dnl 'no' disables versioning. dnl AC_DEFUN([LIBAT_ENABLE_SYMVERS], [ LIBAT_ENABLE(symvers,yes,[=STYLE], [enables symbol versioning of the shared library], [permit yes|no|gnu*|sun]) # If we never went through the LIBAT_CHECK_LINKER_FEATURES macro, then we # don't know enough about $LD to do tricks... AC_REQUIRE([LIBAT_CHECK_LINKER_FEATURES]) # Turn a 'yes' into a suitable default. if test x$enable_symvers = xyes ; then # FIXME The following test is too strict, in theory. if test $enable_shared = no || test "x$LD" = x; then enable_symvers=no else if test $with_gnu_ld = yes ; then enable_symvers=gnu else case ${target_os} in # Sun symbol versioning exists since Solaris 2.5. solaris2.[[5-9]]* | solaris2.1[[0-9]]*) enable_symvers=sun ;; *) enable_symvers=no ;; esac fi fi fi # Check if 'sun' was requested on non-Solaris 2 platforms. if test x$enable_symvers = xsun ; then case ${target_os} in solaris2*) # All fine. ;; *) # Unlikely to work. AC_MSG_WARN([=== You have requested Sun symbol versioning, but]) AC_MSG_WARN([=== you are not targetting Solaris 2.]) AC_MSG_WARN([=== Symbol versioning will be disabled.]) enable_symvers=no ;; esac fi # Check to see if libgcc_s exists, indicating that shared libgcc is possible. if test $enable_symvers != no; then AC_MSG_CHECKING([for shared libgcc]) ac_save_CFLAGS="$CFLAGS" CFLAGS=' -lgcc_s' AC_TRY_LINK(, [return 0;], libat_shared_libgcc=yes, libat_shared_libgcc=no) CFLAGS="$ac_save_CFLAGS" if test $libat_shared_libgcc = no; then cat > conftest.c <&1 >/dev/null \ | sed -n 's/^.* -lgcc_s\([^ ]*\) .*$/\1/p'` changequote([,])dnl rm -f conftest.c conftest.so if test x${libat_libgcc_s_suffix+set} = xset; then CFLAGS=" -lgcc_s$libat_libgcc_s_suffix" AC_TRY_LINK(, [return 0;], libat_shared_libgcc=yes) CFLAGS="$ac_save_CFLAGS" fi fi AC_MSG_RESULT($libat_shared_libgcc) fi # For GNU ld, we need at least this version. The format is described in # LIBAT_CHECK_LINKER_FEATURES above. libat_min_gnu_ld_version=21400 # XXXXXXXXXXX libat_gnu_ld_version=21390 # Check to see if unspecified "yes" value can win, given results above. # Change "yes" into either "no" or a style name. if test $enable_symvers != no && test $libat_shared_libgcc = yes; then if test $with_gnu_ld = yes; then if test $libat_gnu_ld_version -ge $libat_min_gnu_ld_version ; then enable_symvers=gnu elif test $libat_ld_is_gold = yes ; then enable_symvers=gnu else # The right tools, the right setup, but too old. Fallbacks? AC_MSG_WARN(=== Linker version $libat_gnu_ld_version is too old for) AC_MSG_WARN(=== full symbol versioning support in this release of GCC.) AC_MSG_WARN(=== You would need to upgrade your binutils to version) AC_MSG_WARN(=== $libat_min_gnu_ld_version or later and rebuild GCC.) if test $libat_gnu_ld_version -ge 21200 ; then # Globbing fix is present, proper block support is not. dnl AC_MSG_WARN([=== Dude, you are soooo close. Maybe we can fake it.]) dnl enable_symvers=??? AC_MSG_WARN([=== Symbol versioning will be disabled.]) enable_symvers=no else # 2.11 or older. AC_MSG_WARN([=== Symbol versioning will be disabled.]) enable_symvers=no fi fi elif test $enable_symvers = sun; then : All interesting versions of Sun ld support sun style symbol versioning. else # just fail for now AC_MSG_WARN([=== You have requested some kind of symbol versioning, but]) AC_MSG_WARN([=== either you are not using a supported linker, or you are]) AC_MSG_WARN([=== not building a shared libgcc_s (which is required).]) AC_MSG_WARN([=== Symbol versioning will be disabled.]) enable_symvers=no fi fi if test $enable_symvers = gnu; then AC_DEFINE(LIBAT_GNU_SYMBOL_VERSIONING, 1, [Define to 1 if GNU symbol versioning is used for libatomic.]) fi AM_CONDITIONAL(LIBAT_BUILD_VERSIONED_SHLIB, test $enable_symvers != no) AM_CONDITIONAL(LIBAT_BUILD_VERSIONED_SHLIB_GNU, test $enable_symvers = gnu) AM_CONDITIONAL(LIBAT_BUILD_VERSIONED_SHLIB_SUN, test $enable_symvers = sun) AC_MSG_NOTICE(versioning on shared library symbols is $enable_symvers) ])