2.1.2. Build directory
The compilation output (object files, module files, executables) are placed
in a directory given by the Makefile macro BUILD, whose actual value may
depend on the values of other macros. By default, the directory name starts
with build/, and may consist of several subdirectories.
This entire directory hierarchy may grow large, and if the working copy of the
repository is placed under a home directory with limit quota, it may be a good
idea to divert the build directory to some other file system, e.g. as a
subdirectory of the data/ directory:
rm -rf build # if the directory exist locally
mkdir data/build # make subdir
ln -s data/build build # soft link build -> data/build