There used to be customized versions of GNU make here in the dirs:
 make-3.81
 make-3.82-gbuild
 make-4.0-gbuild

These have been moved to the repository hosted at:

 https://git.libreoffice.org/gnu-make-lo

in the branches:

 gnu-make-lo-3.81
 gnu-make-lo-3.82
 gnu-make-lo-4.0

Please find and use these new locations, thanks.