pwd
/Users/gcolpitts/Downloads/ghc-8.2.0.20170404/libffi
# doc says: The commands on this page can all be executed from the testsuite directory.
bash-3.2$ find . -name testsuite
./libffi/build/testsuite
./libffi/build/x86_64-apple-darwin/testsuite
bash-3.2$ pushd libffi/build/x86_64-apple-darwin/testsuite
~/Downloads/ghc-8.2.0.20170404/libffi/build/x86_64-apple-darwin/testsuite ~/Downloads/ghc-8.2.0.20170404
bash-3.2$ make test
make: *** No rule to make target `test'. Stop.
bash-3.2$ popd
~/Downloads/ghc-8.2.0.20170404
bash-3.2$ pushd libffi/build/testsuite
~/Downloads/ghc-8.2.0.20170404/libffi/build/testsuite ~/Downloads/ghc-8.2.0.20170404
bash-3.2$ make test
make: *** No rule to make target `test'. Stop.
bash-3.2$ popd
~/Downloads/ghc-8.2.0.20170404
bash-3.2$ make test
/Applications/Xcode.app/Contents/Developer/usr/bin/make -C testsuite/tests CLEANUP=1 SUMMARY_FILE=../../testsuite_summary.txt
make: *** testsuite/tests: No such file or directory. Stop.
make: *** [test] Error 2
Thanks