Doxygen initialization fails on Ubuntu 20.04 works on 18.04

[mloskot]

In my doc/Jamfile, I have this

.doxygen = [ doxygen.name ] ;
.doxygen ?= doxygen ;

On Ubuntu 20.04, I'm observing the Doxygen initialisation failure:

On Ubuntu 18.04, b2 succeeds to build the dox

Both environments,

• WSL 2
• using the same version of Doxygen and Boost.Build
• using Boost superproject reset to develop branch with latest b2 bootstrapped
• building libs/gil/doc having the libs/gil submodule also at develop branch

This is a peculiar issue but I have no idea what is going on, so documenting it here.

[stale]

Thank you for your contributions. Main development of B2 has moved to https://github.com/bfgroup/b2
This issue has been automatically marked as "transition" to indicate the potential for needing transition to the new B2 development project.