ac_ext problems

[Werner LEMBERG]

At least the MSVC compiler doesn't like `foo.cc' as names for C++
files.  A longer time ago, I've changed the extension of all C++ files
in groff to `foo.cpp', and this indeed works with all tested platforms
(thanks to Nelson Beebe).

Is there any reason to stay with `.cc' as the extension for C++ files
for the autoconf tests, given that `.cpp' is much more portable?

Thus I suggest the patch below.


    Werner


======================================================================


--- c.m4.old    2005-02-27 18:06:35.000000000 +0100
+++ c.m4        2005-05-02 13:04:43.309329920 +0200
@@ -90,7 +90,7 @@
 # ------------
 # CXXFLAGS is not in ac_cpp because -g, -O, etc. are not valid cpp options.
 m4_define([AC_LANG(C++)],
-[ac_ext=cc
+[ac_ext=cpp
 ac_cpp='$CXXCPP $CPPFLAGS'
 ac_compile='$CXX -c $CXXFLAGS $CPPFLAGS conftest.$ac_ext >&AS_MESSAGE_LOG_FD'
 ac_link='$CXX -o conftest$ac_exeext $CXXFLAGS $CPPFLAGS $LDFLAGS 
conftest.$ac_ext $LIBS >&AS_MESSAGE_LOG_FD'