1 # gcc-plugin.m4 -*- Autoconf -*- 2 # Check whether GCC is able to be built with plugin support. 3 4 dnl Copyright (C) 2014 Free Software Foundation, Inc. 5 dnl This file is free software, distributed under the terms of the GNU 6 dnl General Public License. As a special exception to the GNU General 7 dnl Public License, this file may be distributed as part of a program 8 dnl that contains a configuration script generated by Autoconf, under 9 dnl the same distribution terms as the rest of that program. 10 11 # Check for plugin support. 12 # Respects --enable-plugin. 13 # Sets the shell variables enable_plugin and pluginlibs. 14 AC_DEFUN([GCC_ENABLE_PLUGINS], 15 [# Check for plugin support 16 AC_ARG_ENABLE(plugin, 17 [AS_HELP_STRING([--enable-plugin], [enable plugin support])], 18 enable_plugin=$enableval, 19 enable_plugin=yes; default_plugin=yes) 20 21 pluginlibs= 22 plugin_check=yes 23 24 case "${host}" in 25 *-*-mingw*) 26 # Since plugin support under MinGW is not as straightforward as on 27 # other platforms (e.g., we have to link import library, etc), we 28 # only enable it if explicitly requested. 29 if test x"$default_plugin" = x"yes"; then 30 enable_plugin=no 31 elif test x"$enable_plugin" = x"yes"; then 32 # Use make's target variable to derive import library name. 33 pluginlibs='-Wl,--export-all-symbols -Wl,--out-implib=[$]@.a' 34 plugin_check=no 35 fi 36 ;; 37 *-*-darwin*) 38 if test x$build = x$host; then 39 export_sym_check="nm${exeext} -g" 40 elif test x$host = x$target; then 41 export_sym_check="$gcc_cv_nm -g" 42 else 43 export_sym_check= 44 fi 45 ;; 46 *) 47 if test x$build = x$host; then 48 export_sym_check="$ac_cv_prog_OBJDUMP -T" 49 elif test x$host = x$target; then 50 export_sym_check="$gcc_cv_objdump -T" 51 else 52 export_sym_check="$ac_cv_prog_OBJDUMP -T" 53 fi 54 ;; 55 esac 56 57 if test x"$enable_plugin" = x"yes" -a x"$plugin_check" = x"yes"; then 58 59 AC_MSG_CHECKING([for exported symbols]) 60 if test "x$export_sym_check" != x; then 61 echo "int main() {return 0;} int foobar() {return 0;}" > conftest.c 62 ${CC} ${CFLAGS} ${LDFLAGS} conftest.c -o conftest$ac_exeext > /dev/null 2>&1 63 if $export_sym_check conftest$ac_exeext | grep foobar > /dev/null; then 64 : # No need to use a flag 65 AC_MSG_RESULT([yes]) 66 else 67 AC_MSG_RESULT([yes]) 68 AC_MSG_CHECKING([for -rdynamic]) 69 ${CC} ${CFLAGS} ${LDFLAGS} -rdynamic conftest.c -o conftest$ac_exeext > /dev/null 2>&1 70 if $export_sym_check conftest$ac_exeext | grep foobar > /dev/null; then 71 plugin_rdynamic=yes 72 pluginlibs="-rdynamic" 73 else 74 plugin_rdynamic=no 75 enable_plugin=no 76 fi 77 AC_MSG_RESULT([$plugin_rdynamic]) 78 fi 79 else 80 AC_MSG_RESULT([unable to check]) 81 fi 82 83 # Check -ldl 84 saved_LIBS="$LIBS" 85 AC_SEARCH_LIBS([dlopen], [dl]) 86 if test x"$ac_cv_search_dlopen" = x"-ldl"; then 87 pluginlibs="$pluginlibs -ldl" 88 fi 89 LIBS="$saved_LIBS" 90 91 # Check that we can build shared objects with -fPIC -shared 92 saved_LDFLAGS="$LDFLAGS" 93 saved_CFLAGS="$CFLAGS" 94 saved_CXXFLAGS="$CXXFLAGS" 95 case "${host}" in 96 *-*-darwin*) 97 CFLAGS=`echo $CFLAGS | sed s/-mdynamic-no-pic//g` 98 CFLAGS="$CFLAGS -fPIC" 99 CXXFLAGS=`echo $CXXFLAGS | sed s/-mdynamic-no-pic//g` 100 CXXFLAGS="$CXXFLAGS -fPIC" 101 LDFLAGS="$LDFLAGS -shared -undefined dynamic_lookup" 102 ;; 103 *) 104 CFLAGS="$CFLAGS -fPIC" 105 CXXFLAGS="$CXXFLAGS -fPIC" 106 LDFLAGS="$LDFLAGS -fPIC -shared" 107 ;; 108 esac 109 AC_MSG_CHECKING([for -fPIC -shared]) 110 AC_TRY_LINK( 111 [extern int X;],[return X == 0;], 112 [AC_MSG_RESULT([yes]); have_pic_shared=yes], 113 [AC_MSG_RESULT([no]); have_pic_shared=no]) 114 if test x"$have_pic_shared" != x"yes" -o x"$ac_cv_search_dlopen" = x"no"; then 115 pluginlibs= 116 enable_plugin=no 117 fi 118 LDFLAGS="$saved_LDFLAGS" 119 CFLAGS="$saved_CFLAGS" 120 CXXFLAGS="$saved_CXXFLAGS" 121 122 # If plugin support had been requested but not available, fail. 123 if test x"$enable_plugin" = x"no" ; then 124 if test x"$default_plugin" != x"yes"; then 125 AC_MSG_ERROR([ 126 Building GCC with plugin support requires a host that supports 127 -fPIC, -shared, -ldl and -rdynamic.]) 128 fi 129 fi 130 fi 131 ]) 132 133 dnl 134 dnl 135 dnl GCC_PLUGIN_OPTION 136 dnl (SHELL-CODE_HANDLER) 137 dnl 138 AC_DEFUN([GCC_PLUGIN_OPTION],[dnl 139 AC_MSG_CHECKING([for -plugin option]) 140 141 plugin_names="liblto_plugin.so liblto_plugin-0.dll cyglto_plugin-0.dll" 142 plugin_option= 143 for plugin in $plugin_names; do 144 plugin_so=`${CC} ${CFLAGS} --print-prog-name $plugin` 145 if test x$plugin_so = x$plugin; then 146 plugin_so=`${CC} ${CFLAGS} --print-file-name $plugin` 147 fi 148 if test x$plugin_so != x$plugin; then 149 plugin_option="--plugin $plugin_so" 150 break 151 fi 152 done 153 dnl Check if ${AR} $plugin_option rc works. 154 AC_CHECK_TOOL(AR, ar) 155 if test "${AR}" = "" ; then 156 AC_MSG_ERROR([Required archive tool 'ar' not found on PATH.]) 157 fi 158 touch conftest.c 159 ${AR} $plugin_option rc conftest.a conftest.c 160 if test "$?" != 0; then 161 AC_MSG_WARN([Failed: $AR $plugin_option rc]) 162 plugin_option= 163 fi 164 rm -f conftest.* 165 if test -n "$plugin_option"; then 166 $1="$plugin_option" 167 AC_MSG_RESULT($plugin_option) 168 else 169 AC_MSG_RESULT([no]) 170 fi 171 ]) 172
Indexes created Mon Mar 02 05:31:46 UTC 2026