--- /dev/null
+dnl ----------------------------------------------------------------------
+dnl This whole bit snagged from libgfortran.
+
+dnl Check whether the target supports __sync_*_compare_and_swap.
+AC_DEFUN([LIBGOMP_CHECK_SYNC_BUILTINS], [
+ AC_CACHE_CHECK([whether the target supports __sync_*_compare_and_swap],
+ libgomp_cv_have_sync_builtins, [
+ AC_TRY_LINK([], [int foo, bar; bar = __sync_val_compare_and_swap(&foo, 0, 1);],
+ libgomp_cv_have_sync_builtins=yes, libgomp_cv_have_sync_builtins=no)])
+ if test $libgomp_cv_have_sync_builtins = yes; then
+ AC_DEFINE(HAVE_SYNC_BUILTINS, 1,
+ [Define to 1 if the target supports __sync_*_compare_and_swap])
+ fi])
+
+dnl Check whether the target supports hidden visibility.
+AC_DEFUN([LIBGOMP_CHECK_ATTRIBUTE_VISIBILITY], [
+ AC_CACHE_CHECK([whether the target supports hidden visibility],
+ libgomp_cv_have_attribute_visibility, [
+ save_CFLAGS="$CFLAGS"
+ CFLAGS="$CFLAGS -Werror"
+ AC_TRY_COMPILE([void __attribute__((visibility("hidden"))) foo(void) { }],
+ [], libgomp_cv_have_attribute_visibility=yes,
+ libgomp_cv_have_attribute_visibility=no)
+ CFLAGS="$save_CFLAGS"])
+ if test $libgomp_cv_have_attribute_visibility = yes; then
+ AC_DEFINE(HAVE_ATTRIBUTE_VISIBILITY, 1,
+ [Define to 1 if the target supports __attribute__((visibility(...))).])
+ fi])
+
+dnl Check whether the target supports dllexport
+AC_DEFUN([LIBGOMP_CHECK_ATTRIBUTE_DLLEXPORT], [
+ AC_CACHE_CHECK([whether the target supports dllexport],
+ libgomp_cv_have_attribute_dllexport, [
+ save_CFLAGS="$CFLAGS"
+ CFLAGS="$CFLAGS -Werror"
+ AC_TRY_COMPILE([void __attribute__((dllexport)) foo(void) { }],
+ [], libgomp_cv_have_attribute_dllexport=yes,
+ libgomp_cv_have_attribute_dllexport=no)
+ CFLAGS="$save_CFLAGS"])
+ if test $libgomp_cv_have_attribute_dllexport = yes; then
+ AC_DEFINE(HAVE_ATTRIBUTE_DLLEXPORT, 1,
+ [Define to 1 if the target supports __attribute__((dllexport)).])
+ fi])
+
+dnl Check whether the target supports symbol aliases.
+AC_DEFUN([LIBGOMP_CHECK_ATTRIBUTE_ALIAS], [
+ AC_CACHE_CHECK([whether the target supports symbol aliases],
+ libgomp_cv_have_attribute_alias, [
+ AC_TRY_LINK([
+void foo(void) { }
+extern void bar(void) __attribute__((alias("foo")));],
+ [bar();], libgomp_cv_have_attribute_alias=yes, libgomp_cv_have_attribute_alias=no)])
+ if test $libgomp_cv_have_attribute_alias = yes; then
+ AC_DEFINE(HAVE_ATTRIBUTE_ALIAS, 1,
+ [Define to 1 if the target supports __attribute__((alias(...))).])
+ fi])
+
+sinclude(../libtool.m4)
+dnl The lines below arrange for aclocal not to bring an installed
+dnl libtool.m4 into aclocal.m4, while still arranging for automake to
+dnl add a definition of LIBTOOL to Makefile.in.
+ifelse(,,,[AC_SUBST(LIBTOOL)
+AC_DEFUN([AM_PROG_LIBTOOL])
+AC_DEFUN([AC_LIBTOOL_DLOPEN])
+AC_DEFUN([AC_PROG_LD])
+])
+
+dnl ----------------------------------------------------------------------
+dnl This whole bit snagged from libstdc++-v3.
+
+dnl
+dnl LIBGOMP_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([LIBGOMP_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],-,_)[=][$2])
+m4_undefine([_g_switch])dnl
+m4_undefine([_g_help])dnl
+])
+
+
+dnl
+dnl If GNU ld is in use, check to see if tricky linker opts can be used. If
+dnl the native linker is in use, all variables will be defined to something
+dnl safe (like an empty string).
+dnl
+dnl Defines:
+dnl SECTION_LDFLAGS='-Wl,--gc-sections' if possible
+dnl OPT_LDFLAGS='-Wl,-O1' if possible
+dnl LD (as a side effect of testing)
+dnl Sets:
+dnl with_gnu_ld
+dnl libgomp_ld_is_gold (possibly)
+dnl libgomp_gnu_ld_version (possibly)
+dnl
+dnl The last will be a single integer, e.g., version 1.23.45.0.67.89 will
+dnl set libgomp_gnu_ld_version to 12345. Zeros cause problems.
+dnl
+AC_DEFUN([LIBGOMP_CHECK_LINKER_FEATURES], [
+ # If we're not using GNU ld, then there's no point in even trying these
+ # tests. Check for that first. We should have already tested for gld
+ # by now (in libtool), but require it now just to be safe...
+ test -z "$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.
+ libgomp_ld_is_gold=no
+ if $LD --version 2>/dev/null | grep 'GNU gold'> /dev/null 2>&1; then
+ libgomp_ld_is_gold=yes
+ fi
+ changequote(,)
+ ldver=`$LD --version 2>/dev/null | head -1 | \
+ sed -e 's/GNU \(go\)\{0,1\}ld \(version \)\{0,1\}\(([^)]*) \)\{0,1\}\([0-9.][0-9.]*\).*/\4/'`
+ changequote([,])
+ libgomp_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: LIBGOMP_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([LIBGOMP_ENABLE_SYMVERS], [
+
+LIBGOMP_ENABLE(symvers,yes,[=STYLE],
+ [enables symbol versioning of the shared library],
+ [permit yes|no|gnu])
+
+# If we never went through the LIBGOMP_CHECK_LINKER_FEATURES macro, then we
+# don't know enough about $LD to do tricks...
+AC_REQUIRE([LIBGOMP_CHECK_LINKER_FEATURES])
+# FIXME The following test is too strict, in theory.
+if test $enable_shared = no ||
+ test "x$LD" = x ||
+ test x$libgomp_gnu_ld_version = x; then
+ enable_symvers=no
+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;], libgomp_shared_libgcc=yes, libgomp_shared_libgcc=no)
+ CFLAGS="$ac_save_CFLAGS"
+ if test $libgomp_shared_libgcc = no; then
+ cat > conftest.c <<EOF
+int main (void) { return 0; }
+EOF
+changequote(,)dnl
+ libgomp_libgcc_s_suffix=`${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS \
+ -shared -shared-libgcc -o conftest.so \
+ conftest.c -v 2>&1 >/dev/null \
+ | sed -n 's/^.* -lgcc_s\([^ ]*\) .*$/\1/p'`
+changequote([,])dnl
+ rm -f conftest.c conftest.so
+ if test x${libgomp_libgcc_s_suffix+set} = xset; then
+ CFLAGS=" -lgcc_s$libgomp_libgcc_s_suffix"
+ AC_TRY_LINK(, [return 0;], libgomp_shared_libgcc=yes)
+ CFLAGS="$ac_save_CFLAGS"
+ fi
+ fi
+ AC_MSG_RESULT($libgomp_shared_libgcc)
+fi
+
+# For GNU ld, we need at least this version. The format is described in
+# LIBGOMP_CHECK_LINKER_FEATURES above.
+libgomp_min_gnu_ld_version=21400
+# XXXXXXXXXXX libgomp_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 = yes; then
+ if test $with_gnu_ld = yes &&
+ test $libgomp_shared_libgcc = yes;
+ then
+ if test $libgomp_gnu_ld_version -ge $libgomp_min_gnu_ld_version ; then
+ enable_symvers=gnu
+ elif test $libgomp_ld_is_gold = yes ; then
+ enable_symvers=gnu
+ else
+ # The right tools, the right setup, but too old. Fallbacks?
+ AC_MSG_WARN(=== Linker version $libgomp_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(=== $libgomp_min_gnu_ld_version or later and rebuild GCC.)
+ if test $libgomp_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
+ 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
+
+AC_CACHE_CHECK([whether the target supports .symver directive],
+ libgomp_cv_have_as_symver_directive, [
+ AC_TRY_COMPILE([void foo (void); __asm (".symver foo, bar@SYMVER");],
+ [], libgomp_cv_have_as_symver_directive=yes,
+ libgomp_cv_have_as_symver_directive=no)])
+if test $libgomp_cv_have_as_symver_directive = yes; then
+ AC_DEFINE(HAVE_AS_SYMVER_DIRECTIVE, 1,
+ [Define to 1 if the target assembler supports .symver directive.])
+fi
+
+AM_CONDITIONAL(LIBGOMP_BUILD_VERSIONED_SHLIB, test $enable_symvers != no)
+AC_MSG_NOTICE(versioning on shared library symbols is $enable_symvers)
+])
projects / msp430-gcc.git / blobdiff