yet another ddd 3.3.12 MacOS Xt error

[rbd]

I too am getting the same fatal

        Xt error: Unresolved inheritance operation

ddd startup-time error under MacOS as many others have reported here 
recently, using both Sierra and El Capitan. I won't bother repeating the 
same details that everyone else has already reported, mine are essentially 
identical.

I do wonder if this has something to do with the fact that on my systems, 
which use MacPorts for both the ddd and prerequisite OpenMotif package 
installs, the more recent MacPorts OpenMotif package could only be 
installed after I had pre-installed libXt (the source of the ddd error) 
with the modified installation command

        # sudo port install xorg-libXt +flat_namespace

(modified with regard to the newly-required +flat_namespace option).

I have two questions for the ddd-on-MacOS community at large:

(1) Is ddd still working for ANYBODY out there on recent MacOS/ddd/XQuartz 
releases?

(2) Are others, either with or without the ddd Xt inheritance error, using 
the same +flat_namespace libXt install flag as I did? I'm not certain that 
ddd stopped working at exactly the same time as I upgraded my OpenMotif 
with this flag as I use it infrequently under MacOS, but I am suspicious. 
Not sure that it makes any difference as I can't install OpenMotif without 
that flag, but it might point the way to the fix.

Thanks,

Roger Davis
Univ. of Hawaii