make sure that the C++ preprocessor is set up

git-svn-id: svn://svn.lyx.org/lyx/lyx-devel/trunk@19618 a592a061-630c-0410-9148-cb99ea01b6c8

diff --git a/config/lyxinclude.m4 b/config/lyxinclude.m4
index 35344d78ad95e924485258eab31ac8c8de09a616..8793b3d3e5638a2300659feddf2841c72e8963ba 100644 (file)
--- a/config/lyxinclude.m4
+++ b/config/lyxinclude.m4
@@ -156,6 +156,7 @@ fi
 AC_MSG_RESULT($CXX)
 
 AC_PROG_CXX
+AC_PROG_CXXCPP
 
 ### We might want to get or shut warnings.
 AC_ARG_ENABLE(warnings,