brew --build-from-source fails to find gcc on Linux

[rouson]

brew tap fortran/lang && brew install fpm fails on Lubuntu Linux 21.10. The error message recommends building from source, but brew --build-from-source fpm fails and recommends executing brew install gcc. Executing the latter command puts gcc-12, g++-12, and gfortran in /home/linuxbrew/.linuxbrew/bin/ so I created soft links as follows:

cd /home/linuxbrew/.linuxbrew/bin/
ln -s gcc-12 gcc
ln -s g++-12 g++

after which brew install --build-from-source fpm works. Any advice on how to tell Homebrew to use gcc-12 and g++-12 or how to tell Homebrew to create the aforementioned soft links so that I don't have to create them by hand?

In each of the above commands, I actually used -s in place of --build-from-source. The two are equivalent.

[awvwgk]

This might be a question best asked at https://github.com/orgs/Homebrew/discussions