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Clone and checkout latest GOAS version
(Old place: git clone https://gitlab.com/eccc/gem/gem.git)
git clone https://github.com/ECCC-ASTD-MRD/gem.git
cd gem
git checkout -b b_5.1.0-rc6 5.1.0-rc6 # rc6 latest as of 2021/02/10
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Since this directory can get large you must not create it under your home but under you data space.
mkdir -p /path/to/my/work/directory
export MY_WORK_DIR=/path/to/my/work/directory
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Once you change the source code follow the steps above, starting from "Set compiler version and compile".