this compiler broke some years ago and I stopped working on it.

To resurrect it, remove structs, and auto-inc/dec...  simplify down to what is used in tgvectrex.c

NOTE: tailgunner doesn't use any pointers.  At all.

start by stripping a bunch of crap out until what is left is unarguably correct.

then add size types and signedness and a symbol table or AST-equivalent.

test arithmetic with mixed types and promotion of types through expressions, ending in type conversion on assignment or cast