Re: Possible problem with M-x compile

[Richard Stallman]

    cd $CLIENTLIB_BUILDDIR && fmake tests && make

    and this has worked for some time now, on Emacs versions 20 and above.
    In the last two weeks however, the following error is presented:

    cd: No such directory found via CDPATH environment variable

    My shell is /bin/bash, and yes, the environment variable is defined,
    as is CDPATH.

What is the definition of that envvar?

How about adding  pwd>~/foo  to the start of your compile command
in each version and see what it tells you?
Then try both with  echo $CLIENTLIB_BUILDDIR > ~/foo.
Then try both with  echo $CDPATH > ~/foo.
This ought to show what's going on.