gdb/head build, --with-python= FAILs @ "no usable python found " ?

PGNet Dev
2020-03-25T21:51:43Z

with a local/non-distro python 3.8 installed, via pyenv,

pyenv global
3.8-dev
pyenv which python3.8
/usr/local/pyenv/versions/3.8-dev/bin/python3.8
python3.8 -V
Python 3.8.2+
python3.8 -c "import sys; print('\n'.join(sys.path))"
/usr/local/pyenv/versions/3.8-dev/lib/python38.zip
/usr/local/pyenv/versions/3.8-dev/lib/python3.8
/usr/local/pyenv/versions/3.8-dev/lib/python3.8/lib-dynload
/usr/local/pyenv/versions/3.8-dev/lib/python3.8/site-packages

building GDB head

git clone git://sourceware.org/git/binutils-gdb.git
cd binutils-gdb
git log | head
commit 33aa3c10f663b834c9573ede439b2df3c92f0cfe
Author: Tom Tromey <tom@tromey.com>
Date: Wed Mar 25 10:26:38 2020 -0600

Fix error message in compile-object-load.c
...

./configure \
--prefix=/usr/local/gdb \
--with-python=/usr/local/pyenv/versions/3.8-dev/bin/python3.8

...
configure: creating ./config.status
config.status: creating Makefile

fails @ make, "no usable python found",

make V=1

...
checking whether to use MPFR... auto
checking for libmpfr... yes
checking how to link with libmpfr... -lmpfr -lgmp
checking whether to use python... /usr/local/pyenv/versions/3.8-dev/bin/python3.8
checking for python... no
configure: error: no usable python found at /usr/local/pyenv/versions/3.8-dev/bin/python3.8
make[1]: *** [Makefile:11664: configure-gdb] Error 1
make[1]: Leaving directory '/usr/local/src/binutils-gdb'
make: *** [Makefile:854: all] Error 2

In gdb src, the find-python code's a bit challenging to wade through, and possibly (?) outdated -- as I still see multiple references to EOL'd python 2.7x .

IS gdb/head from upstream known to work with python3?

what is the correct config for sufficiently spec'ing a local python install?