* configure.in (LIBRUBY_DLDFLAGS): use -unexported_symbol only

when available.  http://trac.macports.org/ticket/26341

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@29341 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ChangeLog

@@ -1,3 +1,8 @@
+Sat Sep 25 10:30:37 2010  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* configure.in (LIBRUBY_DLDFLAGS): use -unexported_symbol only
+	  when available.  http://trac.macports.org/ticket/26341
+
 Sat Sep 25 10:05:49 2010  KOSAKI Motohiro  <kosaki.motohiro@gmail.com>
 
 	* configure.in: Always add -mieee for Renesas SH4.

configure.in

@@ -302,7 +302,7 @@ AC_CHECK_TOOL(AS, as)
 ASFLAGS=$ASFLAGS
 AC_SUBST(ASFLAGS)
 
-AS_CASE(["$target_os"],[cygwin*|mingw*|darwin*], [ac_cv_prog_ac_ct_OBJCOPY=":"])
+AS_CASE(["$target_os"],[cygwin*|mingw*], [ac_cv_prog_ac_ct_OBJCOPY=":"])
 
 # BSD's ports and MacPorts prefix GNU binutils with 'g'
 AC_CHECK_TOOLS(OBJDUMP, [objdump gobjdump])
@@ -419,6 +419,21 @@ AC_DEFUN(RUBY_TRY_CFLAGS, [
     save_CFLAGS=
 ])
 
+AC_DEFUN(RUBY_TRY_LDFLAGS, [
+    save_LDFLAGS="$LDFLAGS"
+    LDFLAGS="[$]LDFLAGS $1"
+    AC_MSG_CHECKING([whether ]$1[ is accepted])
+    RUBY_WERROR_FLAG([
+    AC_TRY_LINK([$4], [$5],
+	[$2
+	AC_MSG_RESULT(yes)],
+	[$3
+	AC_MSG_RESULT(no)])
+    ])
+    LDFLAGS="$save_LDFLAGS"
+    save_LDFLAGS=
+])
+
 if test "$GCC:${warnflags+set}:no" = yes::no; then
     for wflag in -Wno-unused-parameter -Wno-parentheses -Wpointer-arith -Wwrite-strings \
 		 -Wno-missing-field-initializers -Wshorten-64-to-32 -Wno-long-long; do
@@ -431,6 +446,14 @@ fi
 if test "$GCC" = yes; then
     RUBY_TRY_CFLAGS(-fvisibility=hidden, [RUBY_APPEND_OPTION(XCFLAGS, -fvisibility=hidden)])
 fi
+if test "$GCC" = yes; then
+    if test "$visibility_option" = yes; then
+	RUBY_APPEND_OPTION(XCFLAGS, -fvisibility=hidden)
+    else
+	RUBY_TRY_LDFLAGS(['-Wl,-unexported_symbol,_Init_*'], [visibility_option=ld], [visibility_option=no])
+    fi
+    test "$visibility_option" = no || OBJCOPY=:
+fi
 
 test -z "${ac_env_CFLAGS_set}" -a -n "${cflags+set}" && eval CFLAGS="\"$cflags $ARCH_FLAG\""
 test -z "${ac_env_CXXFLAGS_set}" -a -n "${cxxflags+set}" && eval CXXFLAGS="\"$cxxflags $ARCH_FLAG\""
@@ -2180,6 +2203,10 @@ AS_CASE("$enable_shared", [yes], [
 	LIBRUBY_DLDFLAGS="$LIBRUBY_DLDFLAGS "'-install_name '${libprefix}'/$(LIBRUBY_SO)'
 	LIBRUBY_DLDFLAGS="$LIBRUBY_DLDFLAGS "'-current_version $(MAJOR).$(MINOR).$(TEENY)'
 	LIBRUBY_DLDFLAGS="$LIBRUBY_DLDFLAGS "'-compatibility_version $(ruby_version)'
+	if test "$visibility_option" = ld; then
+	    LIBRUBY_DLDFLAGS="$LIBRUBY_DLDFLAGS "'-Wl,-unexported_symbol,_Init_*'
+	    LIBRUBY_DLDFLAGS="$LIBRUBY_DLDFLAGS "'-Wl,-unexported_symbol,*_threadptr_*'
+	fi
 	LIBRUBY_DLDFLAGS="$LIBRUBY_DLDFLAGS "' $(XLDFLAGS)'
 	LIBRUBY_SO='lib$(RUBY_SO_NAME).dylib'
 	LIBRUBY_ALIASES='lib$(RUBY_BASE_NAME).$(MAJOR).$(MINOR).dylib lib$(RUBY_INSTALL_NAME).dylib'