1dnl ---------------------------------------------------------------------- 2dnl This whole bit snagged from libgfortran. 3 4dnl Check whether the target supports __sync_*_compare_and_swap. 5AC_DEFUN([LIBGOMP_CHECK_SYNC_BUILTINS], [ 6 AC_CACHE_CHECK([whether the target supports __sync_*_compare_and_swap], 7 have_sync_builtins, [ 8 AC_TRY_LINK([], [int foo, bar; bar = __sync_val_compare_and_swap(&foo, 0, 1);], 9 have_sync_builtins=yes, have_sync_builtins=no)]) 10 if test $have_sync_builtins = yes; then 11 AC_DEFINE(HAVE_SYNC_BUILTINS, 1, 12 [Define to 1 if the target supports __sync_*_compare_and_swap]) 13 fi]) 14 15dnl Check whether the target supports hidden visibility. 16AC_DEFUN([LIBGOMP_CHECK_ATTRIBUTE_VISIBILITY], [ 17 AC_CACHE_CHECK([whether the target supports hidden visibility], 18 have_attribute_visibility, [ 19 save_CFLAGS="$CFLAGS" 20 CFLAGS="$CFLAGS -Werror" 21 AC_TRY_COMPILE([void __attribute__((visibility("hidden"))) foo(void) { }], 22 [], have_attribute_visibility=yes, 23 have_attribute_visibility=no) 24 CFLAGS="$save_CFLAGS"]) 25 if test $have_attribute_visibility = yes; then 26 AC_DEFINE(HAVE_ATTRIBUTE_VISIBILITY, 1, 27 [Define to 1 if the target supports __attribute__((visibility(...))).]) 28 fi]) 29 30dnl Check whether the target supports dllexport 31AC_DEFUN([LIBGOMP_CHECK_ATTRIBUTE_DLLEXPORT], [ 32 AC_CACHE_CHECK([whether the target supports dllexport], 33 have_attribute_dllexport, [ 34 save_CFLAGS="$CFLAGS" 35 CFLAGS="$CFLAGS -Werror" 36 AC_TRY_COMPILE([void __attribute__((dllexport)) foo(void) { }], 37 [], have_attribute_dllexport=yes, 38 have_attribute_dllexport=no) 39 CFLAGS="$save_CFLAGS"]) 40 if test $have_attribute_dllexport = yes; then 41 AC_DEFINE(HAVE_ATTRIBUTE_DLLEXPORT, 1, 42 [Define to 1 if the target supports __attribute__((dllexport)).]) 43 fi]) 44 45dnl Check whether the target supports symbol aliases. 46AC_DEFUN([LIBGOMP_CHECK_ATTRIBUTE_ALIAS], [ 47 AC_CACHE_CHECK([whether the target supports symbol aliases], 48 have_attribute_alias, [ 49 AC_TRY_LINK([ 50void foo(void) { } 51extern void bar(void) __attribute__((alias("foo")));], 52 [bar();], have_attribute_alias=yes, have_attribute_alias=no)]) 53 if test $have_attribute_alias = yes; then 54 AC_DEFINE(HAVE_ATTRIBUTE_ALIAS, 1, 55 [Define to 1 if the target supports __attribute__((alias(...))).]) 56 fi]) 57 58sinclude(../libtool.m4) 59dnl The lines below arrange for aclocal not to bring an installed 60dnl libtool.m4 into aclocal.m4, while still arranging for automake to 61dnl add a definition of LIBTOOL to Makefile.in. 62ifelse(,,,[AC_SUBST(LIBTOOL) 63AC_DEFUN([AM_PROG_LIBTOOL]) 64AC_DEFUN([AC_LIBTOOL_DLOPEN]) 65AC_DEFUN([AC_PROG_LD]) 66]) 67 68dnl ---------------------------------------------------------------------- 69dnl This whole bit snagged from libstdc++-v3. 70 71dnl 72dnl LIBGOMP_ENABLE 73dnl (FEATURE, DEFAULT, HELP-ARG, HELP-STRING) 74dnl (FEATURE, DEFAULT, HELP-ARG, HELP-STRING, permit a|b|c) 75dnl (FEATURE, DEFAULT, HELP-ARG, HELP-STRING, SHELL-CODE-HANDLER) 76dnl 77dnl See docs/html/17_intro/configury.html#enable for documentation. 78dnl 79m4_define([LIBGOMP_ENABLE],[dnl 80m4_define([_g_switch],[--enable-$1])dnl 81m4_define([_g_help],[AC_HELP_STRING(_g_switch$3,[$4 @<:@default=$2@:>@])])dnl 82 AC_ARG_ENABLE($1,_g_help, 83 m4_bmatch([$5], 84 [^permit ], 85 [[ 86 case "$enableval" in 87 m4_bpatsubst([$5],[permit ])) ;; 88 *) AC_MSG_ERROR(Unknown argument to enable/disable $1) ;; 89 dnl Idea for future: generate a URL pointing to 90 dnl "onlinedocs/configopts.html#whatever" 91 esac 92 ]], 93 [^$], 94 [[ 95 case "$enableval" in 96 yes|no) ;; 97 *) AC_MSG_ERROR(Argument to enable/disable $1 must be yes or no) ;; 98 esac 99 ]], 100 [[$5]]), 101 [enable_]m4_bpatsubst([$1],-,_)[=][$2]) 102m4_undefine([_g_switch])dnl 103m4_undefine([_g_help])dnl 104]) 105 106 107dnl 108dnl If GNU ld is in use, check to see if tricky linker opts can be used. If 109dnl the native linker is in use, all variables will be defined to something 110dnl safe (like an empty string). 111dnl 112dnl Defines: 113dnl SECTION_LDFLAGS='-Wl,--gc-sections' if possible 114dnl OPT_LDFLAGS='-Wl,-O1' if possible 115dnl LD (as a side effect of testing) 116dnl Sets: 117dnl with_gnu_ld 118dnl libgomp_gnu_ld_version (possibly) 119dnl 120dnl The last will be a single integer, e.g., version 1.23.45.0.67.89 will 121dnl set libgomp_gnu_ld_version to 12345. Zeros cause problems. 122dnl 123AC_DEFUN([LIBGOMP_CHECK_LINKER_FEATURES], [ 124 # If we're not using GNU ld, then there's no point in even trying these 125 # tests. Check for that first. We should have already tested for gld 126 # by now (in libtool), but require it now just to be safe... 127 test -z "$SECTION_LDFLAGS" && SECTION_LDFLAGS='' 128 test -z "$OPT_LDFLAGS" && OPT_LDFLAGS='' 129 AC_REQUIRE([AC_PROG_LD]) 130 AC_REQUIRE([AC_PROG_AWK]) 131 132 # The name set by libtool depends on the version of libtool. Shame on us 133 # for depending on an impl detail, but c'est la vie. Older versions used 134 # ac_cv_prog_gnu_ld, but now it's lt_cv_prog_gnu_ld, and is copied back on 135 # top of with_gnu_ld (which is also set by --with-gnu-ld, so that actually 136 # makes sense). We'll test with_gnu_ld everywhere else, so if that isn't 137 # set (hence we're using an older libtool), then set it. 138 if test x${with_gnu_ld+set} != xset; then 139 if test x${ac_cv_prog_gnu_ld+set} != xset; then 140 # We got through "ac_require(ac_prog_ld)" and still not set? Huh? 141 with_gnu_ld=no 142 else 143 with_gnu_ld=$ac_cv_prog_gnu_ld 144 fi 145 fi 146 147 # Start by getting the version number. I think the libtool test already 148 # does some of this, but throws away the result. 149 changequote(,) 150 ldver=`$LD --version 2>/dev/null | head -1 | \ 151 sed -e 's/GNU ld \(version \)\{0,1\}\(([^)]*) \)\{0,1\}\([0-9.][0-9.]*\).*/\3/'` 152 changequote([,]) 153 libgomp_gnu_ld_version=`echo $ldver | \ 154 $AWK -F. '{ if (NF<3) [$]3=0; print ([$]1*100+[$]2)*100+[$]3 }'` 155 156 # Set --gc-sections. 157 if test "$with_gnu_ld" = "notbroken"; then 158 # GNU ld it is! Joy and bunny rabbits! 159 160 # All these tests are for C++; save the language and the compiler flags. 161 # Need to do this so that g++ won't try to link in libstdc++ 162 ac_test_CFLAGS="${CFLAGS+set}" 163 ac_save_CFLAGS="$CFLAGS" 164 CFLAGS='-x c++ -Wl,--gc-sections' 165 166 # Check for -Wl,--gc-sections 167 # XXX This test is broken at the moment, as symbols required for linking 168 # are now in libsupc++ (not built yet). In addition, this test has 169 # cored on solaris in the past. In addition, --gc-sections doesn't 170 # really work at the moment (keeps on discarding used sections, first 171 # .eh_frame and now some of the glibc sections for iconv). 172 # Bzzzzt. Thanks for playing, maybe next time. 173 AC_MSG_CHECKING([for ld that supports -Wl,--gc-sections]) 174 AC_TRY_RUN([ 175 int main(void) 176 { 177 try { throw 1; } 178 catch (...) { }; 179 return 0; 180 } 181 ], [ac_sectionLDflags=yes],[ac_sectionLDflags=no], [ac_sectionLDflags=yes]) 182 if test "$ac_test_CFLAGS" = set; then 183 CFLAGS="$ac_save_CFLAGS" 184 else 185 # this is the suspicious part 186 CFLAGS='' 187 fi 188 if test "$ac_sectionLDflags" = "yes"; then 189 SECTION_LDFLAGS="-Wl,--gc-sections $SECTION_LDFLAGS" 190 fi 191 AC_MSG_RESULT($ac_sectionLDflags) 192 fi 193 194 # Set linker optimization flags. 195 if test x"$with_gnu_ld" = x"yes"; then 196 OPT_LDFLAGS="-Wl,-O1 $OPT_LDFLAGS" 197 fi 198 199 AC_SUBST(SECTION_LDFLAGS) 200 AC_SUBST(OPT_LDFLAGS) 201]) 202 203 204dnl 205dnl Add version tags to symbols in shared library (or not), additionally 206dnl marking other symbols as private/local (or not). 207dnl 208dnl --enable-symvers=style adds a version script to the linker call when 209dnl creating the shared library. The choice of version script is 210dnl controlled by 'style'. 211dnl --disable-symvers does not. 212dnl + Usage: LIBGOMP_ENABLE_SYMVERS[(DEFAULT)] 213dnl Where DEFAULT is either 'yes' or 'no'. Passing `yes' tries to 214dnl choose a default style based on linker characteristics. Passing 215dnl 'no' disables versioning. 216dnl 217AC_DEFUN([LIBGOMP_ENABLE_SYMVERS], [ 218 219LIBGOMP_ENABLE(symvers,yes,[=STYLE], 220 [enables symbol versioning of the shared library], 221 [permit yes|no|gnu]) 222 223# If we never went through the LIBGOMP_CHECK_LINKER_FEATURES macro, then we 224# don't know enough about $LD to do tricks... 225AC_REQUIRE([LIBGOMP_CHECK_LINKER_FEATURES]) 226# FIXME The following test is too strict, in theory. 227if test $enable_shared = no || 228 test "x$LD" = x || 229 test x$libgomp_gnu_ld_version = x; then 230 enable_symvers=no 231fi 232 233# Check to see if libgcc_s exists, indicating that shared libgcc is possible. 234if test $enable_symvers != no; then 235 AC_MSG_CHECKING([for shared libgcc]) 236 ac_save_CFLAGS="$CFLAGS" 237 CFLAGS=' -lgcc_s' 238 AC_TRY_LINK(, [return 0;], libgomp_shared_libgcc=yes, libgomp_shared_libgcc=no) 239 CFLAGS="$ac_save_CFLAGS" 240 if test $libgomp_shared_libgcc = no; then 241 cat > conftest.c <<EOF 242int main (void) { return 0; } 243EOF 244changequote(,)dnl 245 libgomp_libgcc_s_suffix=`${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS \ 246 -shared -shared-libgcc -o conftest.so \ 247 conftest.c -v 2>&1 >/dev/null \ 248 | sed -n 's/^.* -lgcc_s\([^ ]*\) .*$/\1/p'` 249changequote([,])dnl 250 rm -f conftest.c conftest.so 251 if test x${libgomp_libgcc_s_suffix+set} = xset; then 252 CFLAGS=" -lgcc_s$libgomp_libgcc_s_suffix" 253 AC_TRY_LINK(, [return 0;], libgomp_shared_libgcc=yes) 254 CFLAGS="$ac_save_CFLAGS" 255 fi 256 fi 257 AC_MSG_RESULT($libgomp_shared_libgcc) 258fi 259 260# For GNU ld, we need at least this version. The format is described in 261# LIBGOMP_CHECK_LINKER_FEATURES above. 262libgomp_min_gnu_ld_version=21400 263# XXXXXXXXXXX libgomp_gnu_ld_version=21390 264 265# Check to see if unspecified "yes" value can win, given results above. 266# Change "yes" into either "no" or a style name. 267if test $enable_symvers = yes; then 268 if test $with_gnu_ld = yes && 269 test $libgomp_shared_libgcc = yes; 270 then 271 if test $libgomp_gnu_ld_version -ge $libgomp_min_gnu_ld_version ; then 272 enable_symvers=gnu 273 else 274 # The right tools, the right setup, but too old. Fallbacks? 275 AC_MSG_WARN(=== Linker version $libgomp_gnu_ld_version is too old for) 276 AC_MSG_WARN(=== full symbol versioning support in this release of GCC.) 277 AC_MSG_WARN(=== You would need to upgrade your binutils to version) 278 AC_MSG_WARN(=== $libgomp_min_gnu_ld_version or later and rebuild GCC.) 279 if test $libgomp_gnu_ld_version -ge 21200 ; then 280 # Globbing fix is present, proper block support is not. 281 dnl AC_MSG_WARN([=== Dude, you are soooo close. Maybe we can fake it.]) 282 dnl enable_symvers=??? 283 AC_MSG_WARN([=== Symbol versioning will be disabled.]) 284 enable_symvers=no 285 else 286 # 2.11 or older. 287 AC_MSG_WARN([=== Symbol versioning will be disabled.]) 288 enable_symvers=no 289 fi 290 fi 291 else 292 # just fail for now 293 AC_MSG_WARN([=== You have requested some kind of symbol versioning, but]) 294 AC_MSG_WARN([=== either you are not using a supported linker, or you are]) 295 AC_MSG_WARN([=== not building a shared libgcc_s (which is required).]) 296 AC_MSG_WARN([=== Symbol versioning will be disabled.]) 297 enable_symvers=no 298 fi 299fi 300 301AM_CONDITIONAL(LIBGOMP_BUILD_VERSIONED_SHLIB, test $enable_symvers != no) 302AC_MSG_NOTICE(versioning on shared library symbols is $enable_symvers) 303]) 304