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 libgomp_cv_have_sync_builtins, [ 8 AC_TRY_LINK([], [int foo, bar; bar = __sync_val_compare_and_swap(&foo, 0, 1);], 9 libgomp_cv_have_sync_builtins=yes, libgomp_cv_have_sync_builtins=no)]) 10 if test $libgomp_cv_have_sync_builtins = yes; then 11 AC_DEFINE(HAVE_SYNC_BUILTINS, 1, 12 [Define to 1 if the target supports __sync_*_compare_and_swap]) 13 fi]) 14 15dnl Check whether the target supports hidden visibility. 16AC_DEFUN([LIBGOMP_CHECK_ATTRIBUTE_VISIBILITY], [ 17 AC_CACHE_CHECK([whether the target supports hidden visibility], 18 libgomp_cv_have_attribute_visibility, [ 19 save_CFLAGS="$CFLAGS" 20 CFLAGS="$CFLAGS -Werror" 21 AC_TRY_COMPILE([void __attribute__((visibility("hidden"))) foo(void) { }], 22 [], libgomp_cv_have_attribute_visibility=yes, 23 libgomp_cv_have_attribute_visibility=no) 24 CFLAGS="$save_CFLAGS"]) 25 if test $libgomp_cv_have_attribute_visibility = yes; then 26 AC_DEFINE(HAVE_ATTRIBUTE_VISIBILITY, 1, 27 [Define to 1 if the target supports __attribute__((visibility(...))).]) 28 fi]) 29 30dnl Check whether the target supports dllexport 31AC_DEFUN([LIBGOMP_CHECK_ATTRIBUTE_DLLEXPORT], [ 32 AC_CACHE_CHECK([whether the target supports dllexport], 33 libgomp_cv_have_attribute_dllexport, [ 34 save_CFLAGS="$CFLAGS" 35 CFLAGS="$CFLAGS -Werror" 36 AC_TRY_COMPILE([void __attribute__((dllexport)) foo(void) { }], 37 [], libgomp_cv_have_attribute_dllexport=yes, 38 libgomp_cv_have_attribute_dllexport=no) 39 CFLAGS="$save_CFLAGS"]) 40 if test $libgomp_cv_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 libgomp_cv_have_attribute_alias, [ 49 AC_TRY_LINK([ 50void foo(void) { } 51extern void bar(void) __attribute__((alias("foo")));], 52 [bar();], libgomp_cv_have_attribute_alias=yes, libgomp_cv_have_attribute_alias=no)]) 53 if test $libgomp_cv_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],-,_)[=][$2]) 102m4_undefine([_g_switch])dnl 103m4_undefine([_g_help])dnl 104]) 105 106 107dnl 108dnl If GNU ld is in use, check to see if tricky linker opts can be used. If 109dnl the native linker is in use, all variables will be defined to something 110dnl safe (like an empty string). 111dnl 112dnl Defines: 113dnl SECTION_LDFLAGS='-Wl,--gc-sections' if possible 114dnl OPT_LDFLAGS='-Wl,-O1' if possible 115dnl LD (as a side effect of testing) 116dnl Sets: 117dnl with_gnu_ld 118dnl libgomp_ld_is_gold (possibly) 119dnl libgomp_gnu_ld_version (possibly) 120dnl 121dnl The last will be a single integer, e.g., version 1.23.45.0.67.89 will 122dnl set libgomp_gnu_ld_version to 12345. Zeros cause problems. 123dnl 124AC_DEFUN([LIBGOMP_CHECK_LINKER_FEATURES], [ 125 # If we're not using GNU ld, then there's no point in even trying these 126 # tests. Check for that first. We should have already tested for gld 127 # by now (in libtool), but require it now just to be safe... 128 test -z "$SECTION_LDFLAGS" && SECTION_LDFLAGS='' 129 test -z "$OPT_LDFLAGS" && OPT_LDFLAGS='' 130 AC_REQUIRE([AC_PROG_LD]) 131 AC_REQUIRE([AC_PROG_AWK]) 132 133 # The name set by libtool depends on the version of libtool. Shame on us 134 # for depending on an impl detail, but c'est la vie. Older versions used 135 # ac_cv_prog_gnu_ld, but now it's lt_cv_prog_gnu_ld, and is copied back on 136 # top of with_gnu_ld (which is also set by --with-gnu-ld, so that actually 137 # makes sense). We'll test with_gnu_ld everywhere else, so if that isn't 138 # set (hence we're using an older libtool), then set it. 139 if test x${with_gnu_ld+set} != xset; then 140 if test x${ac_cv_prog_gnu_ld+set} != xset; then 141 # We got through "ac_require(ac_prog_ld)" and still not set? Huh? 142 with_gnu_ld=no 143 else 144 with_gnu_ld=$ac_cv_prog_gnu_ld 145 fi 146 fi 147 148 # Start by getting the version number. I think the libtool test already 149 # does some of this, but throws away the result. 150 libgomp_ld_is_gold=no 151 if $LD --version 2>/dev/null | grep 'GNU gold'> /dev/null 2>&1; then 152 libgomp_ld_is_gold=yes 153 fi 154 changequote(,) 155 ldver=`$LD --version 2>/dev/null | 156 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'` 157 changequote([,]) 158 libgomp_gnu_ld_version=`echo $ldver | \ 159 $AWK -F. '{ if (NF<3) [$]3=0; print ([$]1*100+[$]2)*100+[$]3 }'` 160 161 # Set --gc-sections. 162 if test "$with_gnu_ld" = "notbroken"; then 163 # GNU ld it is! Joy and bunny rabbits! 164 165 # All these tests are for C++; save the language and the compiler flags. 166 # Need to do this so that g++ won't try to link in libstdc++ 167 ac_test_CFLAGS="${CFLAGS+set}" 168 ac_save_CFLAGS="$CFLAGS" 169 CFLAGS='-x c++ -Wl,--gc-sections' 170 171 # Check for -Wl,--gc-sections 172 # XXX This test is broken at the moment, as symbols required for linking 173 # are now in libsupc++ (not built yet). In addition, this test has 174 # cored on solaris in the past. In addition, --gc-sections doesn't 175 # really work at the moment (keeps on discarding used sections, first 176 # .eh_frame and now some of the glibc sections for iconv). 177 # Bzzzzt. Thanks for playing, maybe next time. 178 AC_MSG_CHECKING([for ld that supports -Wl,--gc-sections]) 179 AC_TRY_RUN([ 180 int main(void) 181 { 182 try { throw 1; } 183 catch (...) { }; 184 return 0; 185 } 186 ], [ac_sectionLDflags=yes],[ac_sectionLDflags=no], [ac_sectionLDflags=yes]) 187 if test "$ac_test_CFLAGS" = set; then 188 CFLAGS="$ac_save_CFLAGS" 189 else 190 # this is the suspicious part 191 CFLAGS='' 192 fi 193 if test "$ac_sectionLDflags" = "yes"; then 194 SECTION_LDFLAGS="-Wl,--gc-sections $SECTION_LDFLAGS" 195 fi 196 AC_MSG_RESULT($ac_sectionLDflags) 197 fi 198 199 # Set linker optimization flags. 200 if test x"$with_gnu_ld" = x"yes"; then 201 OPT_LDFLAGS="-Wl,-O1 $OPT_LDFLAGS" 202 fi 203 204 AC_SUBST(SECTION_LDFLAGS) 205 AC_SUBST(OPT_LDFLAGS) 206]) 207 208 209dnl 210dnl Add version tags to symbols in shared library (or not), additionally 211dnl marking other symbols as private/local (or not). 212dnl 213dnl --enable-symvers=style adds a version script to the linker call when 214dnl creating the shared library. The choice of version script is 215dnl controlled by 'style'. 216dnl --disable-symvers does not. 217dnl + Usage: LIBGOMP_ENABLE_SYMVERS[(DEFAULT)] 218dnl Where DEFAULT is either 'yes' or 'no'. Passing `yes' tries to 219dnl choose a default style based on linker characteristics. Passing 220dnl 'no' disables versioning. 221dnl 222AC_DEFUN([LIBGOMP_ENABLE_SYMVERS], [ 223 224LIBGOMP_ENABLE(symvers,yes,[=STYLE], 225 [enables symbol versioning of the shared library], 226 [permit yes|no|gnu]) 227 228# If we never went through the LIBGOMP_CHECK_LINKER_FEATURES macro, then we 229# don't know enough about $LD to do tricks... 230AC_REQUIRE([LIBGOMP_CHECK_LINKER_FEATURES]) 231# FIXME The following test is too strict, in theory. 232if test $enable_shared = no || 233 test "x$LD" = x || 234 test x$libgomp_gnu_ld_version = x; then 235 enable_symvers=no 236fi 237 238# Check to see if libgcc_s exists, indicating that shared libgcc is possible. 239if test $enable_symvers != no; then 240 AC_MSG_CHECKING([for shared libgcc]) 241 ac_save_CFLAGS="$CFLAGS" 242 CFLAGS=' -lgcc_s' 243 AC_TRY_LINK(, [return 0;], libgomp_shared_libgcc=yes, libgomp_shared_libgcc=no) 244 CFLAGS="$ac_save_CFLAGS" 245 if test $libgomp_shared_libgcc = no; then 246 cat > conftest.c <<EOF 247int main (void) { return 0; } 248EOF 249changequote(,)dnl 250 libgomp_libgcc_s_suffix=`${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS \ 251 -shared -shared-libgcc -o conftest.so \ 252 conftest.c -v 2>&1 >/dev/null \ 253 | sed -n 's/^.* -lgcc_s\([^ ]*\) .*$/\1/p'` 254changequote([,])dnl 255 rm -f conftest.c conftest.so 256 if test x${libgomp_libgcc_s_suffix+set} = xset; then 257 CFLAGS=" -lgcc_s$libgomp_libgcc_s_suffix" 258 AC_TRY_LINK(, [return 0;], libgomp_shared_libgcc=yes) 259 CFLAGS="$ac_save_CFLAGS" 260 fi 261 fi 262 AC_MSG_RESULT($libgomp_shared_libgcc) 263fi 264 265# For GNU ld, we need at least this version. The format is described in 266# LIBGOMP_CHECK_LINKER_FEATURES above. 267libgomp_min_gnu_ld_version=21400 268# XXXXXXXXXXX libgomp_gnu_ld_version=21390 269 270# Check to see if unspecified "yes" value can win, given results above. 271# Change "yes" into either "no" or a style name. 272if test $enable_symvers = yes; then 273 if test $with_gnu_ld = yes && 274 test $libgomp_shared_libgcc = yes; 275 then 276 if test $libgomp_gnu_ld_version -ge $libgomp_min_gnu_ld_version ; then 277 enable_symvers=gnu 278 elif test $libgomp_ld_is_gold = yes ; then 279 enable_symvers=gnu 280 else 281 # The right tools, the right setup, but too old. Fallbacks? 282 AC_MSG_WARN(=== Linker version $libgomp_gnu_ld_version is too old for) 283 AC_MSG_WARN(=== full symbol versioning support in this release of GCC.) 284 AC_MSG_WARN(=== You would need to upgrade your binutils to version) 285 AC_MSG_WARN(=== $libgomp_min_gnu_ld_version or later and rebuild GCC.) 286 if test $libgomp_gnu_ld_version -ge 21200 ; then 287 # Globbing fix is present, proper block support is not. 288 dnl AC_MSG_WARN([=== Dude, you are soooo close. Maybe we can fake it.]) 289 dnl enable_symvers=??? 290 AC_MSG_WARN([=== Symbol versioning will be disabled.]) 291 enable_symvers=no 292 else 293 # 2.11 or older. 294 AC_MSG_WARN([=== Symbol versioning will be disabled.]) 295 enable_symvers=no 296 fi 297 fi 298 else 299 # just fail for now 300 AC_MSG_WARN([=== You have requested some kind of symbol versioning, but]) 301 AC_MSG_WARN([=== either you are not using a supported linker, or you are]) 302 AC_MSG_WARN([=== not building a shared libgcc_s (which is required).]) 303 AC_MSG_WARN([=== Symbol versioning will be disabled.]) 304 enable_symvers=no 305 fi 306fi 307 308AC_CACHE_CHECK([whether the target supports .symver directive], 309 libgomp_cv_have_as_symver_directive, [ 310 AC_TRY_COMPILE([void foo (void); __asm (".symver foo, bar@SYMVER");], 311 [], libgomp_cv_have_as_symver_directive=yes, 312 libgomp_cv_have_as_symver_directive=no)]) 313if test $libgomp_cv_have_as_symver_directive = yes; then 314 AC_DEFINE(HAVE_AS_SYMVER_DIRECTIVE, 1, 315 [Define to 1 if the target assembler supports .symver directive.]) 316fi 317 318AM_CONDITIONAL(LIBGOMP_BUILD_VERSIONED_SHLIB, test $enable_symvers != no) 319AC_MSG_NOTICE(versioning on shared library symbols is $enable_symvers) 320]) 321