configuring in-tree gmp/mpfr with "none"?

[Paolo Bonzini]

Jay wrote:
> Andrew, Can you explain more why?

Because at some point, no released version worked on intel macs.

> And then gmp/configure runs flex.
> And then sometimes?always flex tries to run getenv("M4") || "m4".

Yes, Flex uses m4.

> gmp/configure probably should not be setting M4

Yes, I think that setting M4=m4-not-needed should be done only for 
debugging purposes.  Otherwise, GMP should always look for m4 in its 
configure script, and set it to a valid value in the makefile.

Paolo