You need to run the version of gmake you installed, not the one from
before.
DS
There are two basic possibilites here:
1. The shell tries to reduce the time needed to start a
command by caching the paths of 'recently invoked' commands in
order to avoid the need to do a path search everytime. It is
conceivable that you shell is running the old command because
the location is still cached. This can be checked with 'hash'
(prints current contents of the cache) and remedied with 'hash
-r' (dumps the cache).
2. If the gmake build system works the way GNU buildsystems
usually work by default, your newly compiled program should
have landed in /usr/local/bin. Possibly, the other version is
preferred by the shell because the directory it resides in
(should be /usr/bin) precedes /usr/local/bin in the value of
the environment variable PATH or /usr/local/bin isn't included
by default at all.
The 'which' command can be used to determine the actual location of
any particular command which will be executed, given the current value
of PATH.