Unstable behavior on Puppy Linux 32-bit

[mynenik]

A user reports that kForth-32 (version 2.1.0 from current master branch) built on Puppy Linux 32-bit, derived from Ubuntu Bionic (gcc version 7.4.0), will crash with a seg fault if the stack is printed using the word .S . The user also reports that performing the Hayes' Core tests will result in a seg fault crash about halfway through the tests (see forth-src/system-test/core.4th). These problems are not reproducible on any of the following Red Hat-based distributions: RHEL6 32-bit, Centos 7 64-bit, Fedora 30 64-bit.