Bison & M4 version

[Hans Aberg]

The M4 in <ftp://alpha.gnu.org/gnu/bison/> is m4-1.4.2, whereas the  
latest M4 in <http://ftp.gnu.org/pub/gnu/m4/> is m4-1.4.7. Is this  
deliberate, that latest Bison only works on an older M4?

One can also note that <http://directory.fsf.org/gnum4.html> says  
latest (stable) M4 is m4-1.4.4, whereas the latest alpha in <ftp:// 
alpha.gnu.org/gnu/m4/> is m4-1.4.4b, both giving the impression that  
the latest development version is older than the latest release. :-)

So what is the story here?

  Hans Aberg