bug#5191: 23.1.90; Make target compile-main fails under GNU/Linux Kernel 2.6.16

[Dan Nicolaescu <dann@ics.uci.edu>]

Chong Yidong <cyd@stupidchicken.com> writes:

  > Glenn Morris <rgm@gnu.org> writes:
  > 
  > > Chong Yidong wrote:
  > >
  > >> On second thought, I don't think this is a good idea.  Looks like the
  > >> BSDs use ".sinclude" for silent inclusion, and older systems don't even
  > >> support that.
  > >
  > > I think you are right that include is not portable. It's currently
  > > only used in GNUstep builds. I don't think "echo -n" is portable
  > > either. "printf" might be better, I'm not sure.
  > 
  > Another idea: how about autogenerating the ELCFILES Makefile using
  > configure?  Then Makefile.in could just have a line that says
  > 
  > ELCFILES=@elcfiles@
  > 
  > where @elcfiles@ is generated by configure.

Yet another idea: how about we require GNU make?
Other GNU projects require GNU make already, like GCC.
GNU make is widely available on all free systems, and even on
proprietary unixes, I've personally never seen a machine used for
software development that did not have GNU make. 

We can float the idea in the 23.2 release, and make it mandatory a few
months after if we don't get significant pushback.