474 lines
17 KiB
Plaintext
474 lines
17 KiB
Plaintext
# 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 <sys/types.h>
|
|
#include <sys/mman.h>
|
|
#include <unistd.h>
|
|
|
|
#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/GNU gold /GNU ld /;s/GNU ld version /GNU ld /;s/GNU ld ([^)]*) /GNU ld /;s/GNU ld \([0-9.][0-9.]*\).*/\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/GNU gold /GNU ld /;s/GNU ld version /GNU ld /;s/GNU ld ([^)]*) /GNU ld /;s/GNU ld \([0-9.][0-9.]*\).*/\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 $libat_shared_libgcc = no; then
|
|
cat > conftest.c <<EOF
|
|
int main (void) { return 0; }
|
|
EOF
|
|
changequote(,)dnl
|
|
libat_libgcc_s_suffix=`${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS \
|
|
-shared -shared-libgcc -o conftest.so \
|
|
conftest.c -v 2>&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)
|
|
])
|