diff options
Diffstat (limited to 'm4/visibility.m4')
| -rw-r--r-- | m4/visibility.m4 | 140 |
1 files changed, 140 insertions, 0 deletions
diff --git a/m4/visibility.m4 b/m4/visibility.m4 new file mode 100644 index 0000000..48188cd --- /dev/null +++ b/m4/visibility.m4 @@ -0,0 +1,140 @@ +AC_DEFUN([SUDO_SYMBOL_VISIBILITY], [ + dnl + dnl Check for symbol visibility support. + dnl This test relies on AC_LANG_WERROR + dnl + if test -n "$GCC"; then + AX_CHECK_COMPILE_FLAG([-fvisibility=hidden], [ + AC_DEFINE(HAVE_DSO_VISIBILITY) + AX_APPEND_FLAG([-fvisibility=hidden], [CFLAGS]) + LT_LDEXPORTS= + LT_LDDEP= + ]) + else + case "$host_os" in + hpux*) + AX_CHECK_COMPILE_FLAG([-Bhidden_def], [ + # HP-UX cc may not allow __declspec(dllexport) to be + # used in conjunction with #pragma HP_DEFINED_EXTERNAL + # when redefining standard libc functions. + AC_CACHE_CHECK([whether __declspec(dllexport) can be used when overriding libc functions], + [sudo_cv_var_hpux_declspec_libc_function], + [ + _CFLAGS="$CFLAGS" + CFLAGS="${CFLAGS} -Bhidden_def" + AC_COMPILE_IFELSE([AC_LANG_SOURCE([[#include <stdlib.h> + __declspec(dllexport) char * getenv(const char *n) { return NULL; }]])], [ + sudo_cv_var_hpux_declspec_libc_function=yes + ], [ + sudo_cv_var_hpux_declspec_libc_function=no + ]) + CFLAGS="$_CFLAGS" + ] + ) + if test "$sudo_cv_var_hpux_declspec_libc_function" = "yes"; then + AC_DEFINE(HAVE_DSO_VISIBILITY) + AX_APPEND_FLAG([-Bhidden_def], [CFLAGS]) + LT_LDEXPORTS= + LT_LDDEP= + fi + ]) + ;; + solaris2*) + AX_CHECK_COMPILE_FLAG([-xldscope=hidden], [ + AC_DEFINE(HAVE_DSO_VISIBILITY) + AX_APPEND_FLAG([-xldscope=hidden], [CFLAGS]) + LT_LDEXPORTS= + LT_LDDEP= + ]) + ;; + esac + fi + + dnl + dnl Check whether ld supports version scripts (most ELF linkers). + dnl If possible, we use this even if the compiler has symbol visibility + dnl support so we will notice mismatches between the exports file and + dnl sudo_dso_public annotations in the source code. + dnl This test relies on AC_LANG_WERROR + dnl + if test "$lt_cv_prog_gnu_ld" = "yes"; then + AC_CACHE_CHECK([whether ld supports anonymous map files], + [sudo_cv_var_gnu_ld_anon_map], + [ + sudo_cv_var_gnu_ld_anon_map=no + cat > conftest.map <<-EOF + { + global: foo; + local: *; + }; + EOF + _CFLAGS="$CFLAGS" + CFLAGS="$CFLAGS $lt_prog_compiler_pic" + _LDFLAGS="$LDFLAGS" + LDFLAGS="$LDFLAGS $lt_prog_compiler_pic -shared -Wl,--version-script,./conftest.map" + AC_LINK_IFELSE([AC_LANG_PROGRAM([[int foo;]], [[]])], + [sudo_cv_var_gnu_ld_anon_map=yes]) + CFLAGS="$_CFLAGS" + LDFLAGS="$_LDFLAGS" + rm -f conftest.map + ] + ) + if test "$sudo_cv_var_gnu_ld_anon_map" = "yes"; then + LT_LDDEP="\$(shlib_map)"; LT_LDEXPORTS="-Wl,--version-script,\$(shlib_map)" + fi + else + case "$host_os" in + solaris2*) + AC_CACHE_CHECK([whether ld supports anonymous map files], + [sudo_cv_var_solaris_ld_anon_map], + [ + sudo_cv_var_solaris_ld_anon_map=no + cat > conftest.map <<-EOF + { + global: foo; + local: *; + }; + EOF + _CFLAGS="$CFLAGS" + CFLAGS="$CFLAGS $lt_prog_compiler_pic" + _LDFLAGS="$LDFLAGS" + LDFLAGS="$LDFLAGS -shared -Wl,-M,./conftest.map" + AC_LINK_IFELSE([AC_LANG_PROGRAM([[int foo;]], [[]])], + [sudo_cv_var_solaris_ld_anon_map=yes]) + CFLAGS="$_CFLAGS" + LDFLAGS="$_LDFLAGS" + rm -f conftest.map + ] + ) + if test "$sudo_cv_var_solaris_ld_anon_map" = "yes"; then + LT_LDDEP="\$(shlib_map)"; LT_LDEXPORTS="-Wl,-M,\$(shlib_map)" + fi + ;; + hpux*) + AC_CACHE_CHECK([whether ld supports controlling exported symbols], + [sudo_cv_var_hpux_ld_symbol_export], + [ + sudo_cv_var_hpux_ld_symbol_export=no + echo "+e foo" > conftest.opt + _CFLAGS="$CFLAGS" + CFLAGS="$CFLAGS $lt_prog_compiler_pic" + _LDFLAGS="$LDFLAGS" + if test -n "$GCC"; then + LDFLAGS="$LDFLAGS -shared -Wl,-c,./conftest.opt" + else + LDFLAGS="$LDFLAGS -b -Wl,-c,./conftest.opt" + fi + AC_LINK_IFELSE([AC_LANG_PROGRAM([[int foo;]], [[]])], + [sudo_cv_var_hpux_ld_symbol_export=yes]) + CFLAGS="$_CFLAGS" + LDFLAGS="$_LDFLAGS" + rm -f conftest.opt + ] + ) + if test "$sudo_cv_var_hpux_ld_symbol_export" = "yes"; then + LT_LDDEP="\$(shlib_opt)"; LT_LDEXPORTS="-Wl,-c,\$(shlib_opt)" + fi + ;; + esac + fi +]) |