THRIFT-507. Only use Boost for building the C++ library

- Make AX_BOOST_BASE warn instead of fataling if Boost is not found.
- If Boost is not found, disable compilation of the C++ library.
- Do not use CPPFLAGS or LDFLAGS from Boost when building the compiler.

git-svn-id: https://svn.apache.org/repos/asf/incubator/thrift/trunk@991253 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/aclocal/ax_boost_base.m4 b/aclocal/ax_boost_base.m4
index e56bb73..c96d1b6 100644
--- a/aclocal/ax_boost_base.m4
+++ b/aclocal/ax_boost_base.m4
@@ -24,6 +24,7 @@
 # LAST MODIFICATION
 #
 #   2007-07-28
+#   Modified for use in Thrift
 #
 # COPYLEFT
 #
@@ -181,9 +182,9 @@
 
 	if test "$succeeded" != "yes" ; then
 		if test "$_version" = "0" ; then
-			AC_MSG_ERROR([[We could not detect the boost libraries (version $boost_lib_version_req_shorten or higher). If you have a staged boost library (still not installed) please specify \$BOOST_ROOT in your environment and do not give a PATH to --with-boost option.  If you are sure you have boost installed, then check your version number looking in <boost/version.hpp>. See http://randspringer.de/boost for more documentation.]])
+			AC_MSG_WARN([[We could not detect the boost libraries (version $boost_lib_version_req_shorten or higher). If you have a staged boost library (still not installed) please specify \$BOOST_ROOT in your environment and do not give a PATH to --with-boost option.  If you are sure you have boost installed, then check your version number looking in <boost/version.hpp>. See http://randspringer.de/boost for more documentation.]])
 		else
-			AC_MSG_NOTICE([Your boost libraries seems to old (version $_version).])
+			AC_MSG_WARN([Your boost libraries seems to old (version $_version).])
 		fi
 	else
 		AC_SUBST(BOOST_CPPFLAGS)