id summary reporter owner description type status priority milestone component version resolution keywords cc difficulty 803 setters like set-cdr! don't invalidate type information sjamaan "The following program, when compiled with specialization, prints {{#t}}. It prints #f in all other cases: {{{ #!scm (let ((x (list 'a))) (set-cdr! x x) (print (list? x))) }}} If possible, set-car! and set-cdr! should have roughly the same effect as set! (and so should vector-set! but I couldn't reproduce a similar error with that, so I guess that's already taken care of, somehow) I'll look into it in more detail but wanted to create a ticket so we don't forget about this." defect closed major 4.9.0 compiler 4.7.x fixed scrutinizer, optimizations