Daily bump.
[official-gcc.git] / config / gcc-plugin.m4
blob8f278719118277230f493e0185fb2a09593e9e45
1 # gcc-plugin.m4 -*- Autoconf -*-
2 # Check whether GCC is able to be built with plugin support.
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.
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=$enableval,
19    enable_plugin=yes; default_plugin=yes)
21    pluginlibs=
22    plugin_check=yes
24    case "${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$host; then
48          export_sym_check="objdump${exeext} -T"
49        elif test x$host = x$target; then
50          export_sym_check="$gcc_cv_objdump -T"
51        else
52          export_sym_check=
53        fi
54      ;;
55    esac
57    if test x"$enable_plugin" = x"yes" -a x"$plugin_check" = x"yes"; then
59      AC_MSG_CHECKING([for exported symbols])
60      if test "x$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([$plugin_rdynamic])
78        fi
79      else
80        AC_MSG_RESULT([unable to check])
81      fi
83      # Check -ldl
84      saved_LIBS="$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="$saved_LIBS"
91      # Check that we can build shared objects with -fPIC -shared
92      saved_LDFLAGS="$LDFLAGS"
93      saved_CFLAGS="$CFLAGS"
94      case "${host}" in
95        *-*-darwin*)
96          CFLAGS=`echo $CFLAGS | sed s/-mdynamic-no-pic//g`
97          CFLAGS="$CFLAGS -fPIC"
98          LDFLAGS="$LDFLAGS -shared -undefined dynamic_lookup"
99        ;;
100        *)
101          CFLAGS="$CFLAGS -fPIC"
102          LDFLAGS="$LDFLAGS -fPIC -shared"
103        ;;
104      esac
105      AC_MSG_CHECKING([for -fPIC -shared])
106      AC_TRY_LINK(
107        [extern int X;],[return X == 0;],
108        [AC_MSG_RESULT([yes]); have_pic_shared=yes],
109        [AC_MSG_RESULT([no]); have_pic_shared=no])
110      if test x"$have_pic_shared" != x"yes" -o x"$ac_cv_search_dlopen" = x"no"; then
111        pluginlibs=
112        enable_plugin=no
113      fi
114      LDFLAGS="$saved_LDFLAGS"
115      CFLAGS="$saved_CFLAGS"
117      # If plugin support had been requested but not available, fail.
118      if test x"$enable_plugin" = x"no" ; then
119        if test x"$default_plugin" != x"yes"; then
120          AC_MSG_ERROR([
121    Building GCC with plugin support requires a host that supports
122    -fPIC, -shared, -ldl and -rdynamic.])
123        fi
124      fi
125    fi