David Abrahams wrote:
This I don't understand anymore. The code in question is:
some_spirit_grammar g; boost::spirit::pt_parse(it, end, g);
the programm crashes inside pt_parse because of g == 0xcccccccc (destroyed object), where pt_parse takes 'g' by const reference. Initially 'g' was defined as a function local static instance, which I've removed now because I had the suspicion CW8.x couldn't handle that correctly.
Any clues? Regards Hartmut
Are you running into the CW 8.3 "CRTP bug" where casting to a derived class reference can induce a copy?
That's possible, since Spirit passes the parser<> base class around and casts it to the correct derived class (type supplied through CRTP) when needed. Is there a known workaround?
Yes, use
*static_cast<Derived*>(this)
instead of
static_cast<Derived&>(*this)
Spirit does it this way (*static_cast<Derived*>(this)) and Wave simply relies on Spirit. Seems that it's not the CRTP bug then. *sigh*
OTOH all the Spirit tests should fail if this assumption is correct.
I wouldn't count on it. Temporaries can be deceptive. The memory may remain valid after destruction.
Agreed. Regards Hartmut