I installed XQuartz and with brew updated also installed ddd.
Rebooted and:
~ $: ddd
Error: Unresolved inheritance operation
Xt error (Unresolved inheritance operation).
Oops! You have found a bug in DDD.
If you can reproduce this bug, please send a bug report
to <address@hidden>, giving a subject like
DDD 3.3.12 (i386-apple-darwin17.3.0) gets Xt error
To enable us to fix the bug, you should include the following information:
* What you were doing to get this message. Report all the facts.
* The contents of the `~/.ddd/log' file as generated by this session.
Please read also the section "Reporting Bugs" in the DDD manual.
We thank you for your support.
ddd: Cannot save options
~ $:
Content of ~.ddd/lob
GNU DDD 3.3.12 (i386-apple-darwin17.3.0)
Copyright (C) 1995-1999 Technische Universit�t Braunschweig, Germany.
Copyright (C) 1999-2001 Universit�t Passau, Germany.
Copyright (C) 2001 Universit�t des Saarlandes, Germany.
Copyright (C) 2001-2009 Free Software Foundation, Inc.
Compiled with GCC 4.2.1 Compatible Apple LLVM 9.0.0 (clang-900.0.39.2)
Requires X11R6, Xt11R6, Motif 2.3.8 (Motif Version 2.3.8)
Includes XPM 3.4.11, Athena Panner (7000002L), Manual, App defaults, DDD core
Built 2018-03-13 by (unknown).
$ ddd
! Xt error: Unresolved inheritance operation
! Xt error
! Cannot save options