+- run `make maintainer-check' which:
+ - runs `valgrind -q bison' to run Bison under Valgrind.
+ - runs the parsers under Valgrind.
+ - runs the test suite with G++ as C compiler...
+
+- run `make maintainer-push-check', which runs `make maintainer-check'
+ while activating the push implementation and its pull interface wrappers
+ in many test cases that were originally written to exercise only the
+ pull implementation. This makes certain the push implementation can
+ perform every task the pull implementation can.