Re: GNU poke 2.0.92 invokes undefined behaviour on signed integers

[Bruno Haible]

On Linux/x86_64, with GCC 9.3 and CC="gcc -ftrapv" (which detects specific
kinds of undefined behaviour with signed integers) produces:

                === poke Summary ===

# of expected passes            6308
# of unexpected failures        6
# of unsupported tests          3

The failed tests are:

Running /tmp/poke-2.0.92/testsuite/poke.pkl/pkl.exp ...
FAIL: poke.pkl/cdiv-integers-overflow-1.pk execution test
FAIL: poke.pkl/div-integers-overflow-1.pk execution test
FAIL: poke.pkl/mod-integers-overflow-1.pk execution test
FAIL: poke.pkl/neg-int-overflow-1.pk execution test
FAIL: poke.pkl/sl-integers-4.pk execution test
FAIL: poke.pkl/sub-integers-overflow-1.pk execution test

In all 6 cases the poke.log shows that abort() was invoked.