GNU make is pretty much a SysV make. SysV make and BSD make seem to have split between 4.2BSD and 4.3BSD, making the compatible featureset three decades old. The two can't even agree on their syntax for if statements, let alone anything else interesting.
The feature depended on tests running in a predictable location at a predictable depth, but since 38e7337 they don't. Plus the feature isn't needed on VMS systems released in the last twelve years or so. So it seems time to say goodbye. Folks on VAX or VMS versions prior to 7.2 still have years of good hunting in the forests of EUMM 6.77 and earlier and Perl 5.18.x and earlier. And in fact they can still run as well as they do now but the ability to run tests may be diminished.
At least on VMS, where the contents of DEFINE get added to it because you have to have one /DEFINE qualifier containing all the defines coming in from either CCFLAGS or DEFINE. So test that what we got from PERL_MM_OPT is present in rather than is exactly equivalent to what ends up in CCFLAGS.