Fix gnu versioned namespace mode 03/03

[François Dumont]

    libstdc++: Review configuration options to control abi
    --disable-libstdcxx-dual-abi default to 'new' abi mode.

    --with-default-libstdcxx-abi consider the requested abi mode regardless
    of --disable-libstdcxx-dual-abi usage.

    libstdc++-v3/ChangeLog

            * acinclude.m4 (GLIBCXX_ENABLE_LIBSTDCXX_DUAL_ABI): Set
            default_libstdcxx_abi to "new" when not using versioned 
namespace.
            (GLIBCXX_DEFAULT_ABI): Remove enable_libstdcxx_dual_abi=yes 
check.
            * configure: Regenerate.

Ok to commit ?

François

diff --git a/libstdc++-v3/acinclude.m4 b/libstdc++-v3/acinclude.m4
index 3da1d5f1a01..0ba755b08d2 100644
--- a/libstdc++-v3/acinclude.m4
+++ b/libstdc++-v3/acinclude.m4
@@ -4867,7 +4867,7 @@ dnl
 dnl Control whether the library should define symbols for old and new ABIs.
 dnl This affects definitions of strings, stringstreams and locale facets.
 dnl
-dnl --disable-libstdcxx-dual-abi will use old ABI for all types.
+dnl --disable-libstdcxx-dual-abi will use new ABI for all types.
 dnl
 dnl Defines:
 dnl  _GLIBCXX_USE_DUAL_ABI (always defined, either to 1 or 0)
@@ -4883,7 +4883,7 @@ AC_DEFUN([GLIBCXX_ENABLE_LIBSTDCXX_DUAL_ABI], [
   else
     if test x"$enable_libstdcxx_dual_abi" != xyes; then
       AC_MSG_NOTICE([dual ABI is disabled])
-      default_libstdcxx_abi="gcc4-compatible"
+      default_libstdcxx_abi="new"
     fi
   fi
   GLIBCXX_CONDITIONAL(ENABLE_DUAL_ABI, test $enable_libstdcxx_dual_abi = yes)
@@ -4898,7 +4898,6 @@ dnl Defines:
 dnl  _GLIBCXX_USE_CXX11_ABI (always defined, either to 1 or 0)
 dnl
 AC_DEFUN([GLIBCXX_DEFAULT_ABI], [
-  if test x$enable_libstdcxx_dual_abi = xyes; then
   AC_MSG_CHECKING([for default std::string ABI to use])
   AC_ARG_WITH([default-libstdcxx-abi],
     AS_HELP_STRING([--with-default-libstdcxx-abi],
@@ -4912,7 +4911,6 @@ AC_DEFUN([GLIBCXX_DEFAULT_ABI], [
      ],
     [default_libstdcxx_abi="new"])
   AC_MSG_RESULT(${default_libstdcxx_abi})
-  fi
   if test $default_libstdcxx_abi = "new"; then
     glibcxx_cxx11_abi=1
     glibcxx_cxx98_abi=0
diff --git a/libstdc++-v3/configure b/libstdc++-v3/configure
index 341a8b2cb25..89201086507 100755
--- a/libstdc++-v3/configure
+++ b/libstdc++-v3/configure
@@ -51276,13 +51276,12 @@ $as_echo "$as_me: dual ABI is disabled" >&6;}
     if test x"$enable_libstdcxx_dual_abi" != xyes; then
       { $as_echo "$as_me:${as_lineno-$LINENO}: dual ABI is disabled" >&5
 $as_echo "$as_me: dual ABI is disabled" >&6;}
-      default_libstdcxx_abi="gcc4-compatible"
+      default_libstdcxx_abi="new"
     fi
   fi
 
 
 
-  if test x$enable_libstdcxx_dual_abi = xyes; then
   { $as_echo "$as_me:${as_lineno-$LINENO}: checking for default std::string 
ABI to use" >&5
 $as_echo_n "checking for default std::string ABI to use... " >&6; }
 
@@ -51301,7 +51300,6 @@ fi
 
   { $as_echo "$as_me:${as_lineno-$LINENO}: result: ${default_libstdcxx_abi}" 
>&5
 $as_echo "${default_libstdcxx_abi}" >&6; }
-  fi
   if test $default_libstdcxx_abi = "new"; then
     glibcxx_cxx11_abi=1
     glibcxx_cxx98_abi=0