Porting to a new platform

"Joachim Schmitz" [off-list ref] writes:

- HP NonStop is lacking poll(),...
- HP NonStop is lacking getrlimit(), fsync(), setitimer()...

I would check compat/win32 and friends and see what other platforms
that lack this and that do, if I were you.

so telling configure to search for c99  should help here.

In general, the top-level Makefile is designed to be usable without
ever worrying about "configure" mess.  Just define CC for the
platform section there, and optionally add a support to flip the
same in configure.ac.  This applies equally to other conditional
compilation options you may have to add to support your platform.