cl -c -o trouble in libtool am-subdir.at

[Peter Rosin]

Hi!

For some years now, I've been working on and off on adding MSVC
support w/o wrapper scripts to libtool (see the pr-msvc-support
branch in libtool git) and have run into an issue that has been
brought up here before.

http://lists.gnu.org/archive/html/automake/2007-06/msg00083.html

I was trying to fix the am-subdir.at test in the libtool testsuite.
That test uses C++ and compiles in subdirs, so it's really no big
surprise that MSVC is in trouble there.

In short, MSVC w/o wrapper needs AM_PROG_CXX_C_O for that test to work
(a few other minor tweeks might also be needed, methinks...).

Can such a macro be added to automake, please?

Cheers,
Peter (not subscribed, please CC)