Improve detection of C++11 compiler and set appropriate flags to use C++11/C++0x features

git-svn-id: https://swig.svn.sourceforge.net/svnroot/swig/branches/gsoc2009-matevz@13867 626c5289-ae23-0410-ae9c-e8d60b6d4f22

Examples/Makefile.in

@@ -24,7 +24,7 @@
 TARGET     =
 CC         = @CC@
 CXX        = @CXX@
-CFLAGS     = @PLATFLAGS@
+CFLAGS     = @PLATCFLAGS@
 CXXFLAGS   = @PLATCXXFLAGS@
 prefix     = @prefix@
 exec_prefix= @exec_prefix@

Examples/guile/Makefile.in

@@ -6,7 +6,7 @@ top_srcdir	= @top_srcdir@
 SWIG		= ../$(top_srcdir)/preinst-swig
 CC		= @CC@
 CXX		= @CXX@
-CFLAGS		= @PLATFLAGS@
+CFLAGS		= @PLATCFLAGS@
 GUILEINCLUDE	= @GUILEINCLUDE@
 GUILELINK	= @GUILELINK@
 SWIGOPT		=

configure.in

@@ -314,16 +314,21 @@ case $host in
 esac
 
 # Optional CFLAGS used to silence compiler warnings on some platforms.
+AC_SUBST(PLATCFLAGS)
+PLATCFLAGS=
 
-AC_SUBST(PLATFLAGS)
-PLATFLAGS=
-
-# Add switch to enable C++0x support
+# Add switch if necessary to enable C++11 support - just for tests
+AC_LANG_PUSH([C++])
+CXXFLAGS_SAVED=$CXXFLAGS
+AX_CXX_COMPILE_STDCXX_11([noext], [nostop])
+CXXFLAGS=$CXXFLAGS_SAVED
+AC_LANG_POP([C++])
 AC_SUBST(PLATCXXFLAGS)
-if test "$GCC" = yes; then
-    PLATCXXFLAGS=$PLATFLAGS" -std=c++0x "
+AC_SUBST(HAVE_CXX11_COMPILER)
+if test x"$CXX11FLAGS" = x; then
+  PLATCXXFLAGS="$PLATCFLAGS"
 else
-    PLATCXXFLAGS=$PLATFLAGS
+  PLATCXXFLAGS="$CXX11FLAGS $PLATCFLAGS"
 fi
 
 # Check for specific libraries.   Used for SWIG examples