complie with mpfr support

[Ivan Molineris]

Hi all,
I would like to avoid problems like this one:
https://stackoverflow.com/questions/20684195/awk-and-numeric-comparison-with-number-less-than-1-7e-308

If I understood well, if gawk is compiled with mpfr support, invoking it
with -M solve the problem.

I tried to install mpfr whit
$ conda create -n gawk-compile -c conda-forge mpfr
and to configure ad compile gawk in this environment, but -M is still not
available.
How can I compile gawk with mpfr?

Regards