On Sat, 13 Nov 1999, Jason Thorpe wrote:

> On Sat, 13 Nov 1999 06:16:31 -0600 (CST) 
>  Frederick Bruckman <fb@enteract.com> wrote:
> 
>  > The info file for "gcc" lists both `.cxx' and `.cpp' as valid C++
>  > suffixes, so we probably should recognize them both.
> 
> No, the sys.mk rules should do what POSIX says.  That's what the reference
> should be; not the GCC info file.

Fair enough. Would someone check what POSIX says about this?

According to the Single Unix Spec, conforming implementations must
support ".SUFFIXES: .o .c .y .l .a .sh .f .c~ .y~ .l~ .sh~ .f~",
but it's OK to provide additional rules and macros. We seem to be
missing the .*~ ones--does anyone actually use those?