diff --git a/configure.in b/configure.in
index 6d6155f81425..09600f126def 100644
--- a/configure.in
+++ b/configure.in
@@ -49,6 +49,10 @@ PathFormat()
     fi
 }
 
+if test -n "$SOLARENV" ; then
+    AC_MSG_ERROR([You have sourced config_host.mk in this shell.  This may lead to trouble, please run in a fresh (login) shell.])
+fi
+
 echo "********************************************************************"
 echo "*"
 echo "*   Running ${PACKAGE_NAME} build configuration."