The preprocessor symbol BUG_TOOBIG controls compilation of code we had
to insert to avoid "yacc stack overflow" errors in the SunOS 3.5 C compiler.
Release 2.0 produces very complicated expressions for the inline copy
constructors it generates for deeply-derived classes. Explicitly defining
non-inline copy constructors solves the problem. If you are a C compiler
vendor, please make your tables big enough to handle the C code generated by
the AT&T C++ Translator!