diff options
| -rw-r--r-- | lib.c | 20 |
1 files changed, 20 insertions, 0 deletions
@@ -571,6 +571,20 @@ static int seq_iter_get_oop(seq_iter_t *it, val *pval) { val iter = it->ui.iter; + /* The assignments to ui.iter and ui.next are wrong if the it structure is + * embedded inside a heap-allocated iterator object. The object could be a + * gen 1 object, whereas the value being assigned could be a gen 0. + * + * The only way this can happen is if the obsolescent seq-begin function is + * used on an object that supports the iter-begin method. The seq-begin + * constructor is the only function which creates a heap-allocated iterator + * which is initialized via seq_iter_init_with_info, which binds this + * seq_iter_get_oop function and its sisters. + * + * The other heap-allocated iterator type is iter-begin. iter-begin applies + * its own handling for OOP iterators; it doesn't set up seq_iter_t for + * objects of that type, and so these functions are not used. + */ if (it->ul.next != nao) { val iter_step_meth = get_special_required_slot(iter, iter_step_m); *pval = it->ul.next; @@ -597,6 +611,8 @@ static int seq_iter_peek_oop(seq_iter_t *it, val *pval) { val iter = it->ui.iter; + /* See comment in seq_iter_get_oop */ + if (it->ul.next != nao) { *pval = it->ul.next; return 1; @@ -629,6 +645,8 @@ static int seq_iter_get_fast_oop(seq_iter_t *it, val *pval) *pval = item; } + /* See comment in seq_iter_get_oop */ + it->ui.iter = funcall1(iter_step_meth, iter); it->ul.next = nao; return 1; @@ -646,6 +664,8 @@ static int seq_iter_peek_fast_oop(seq_iter_t *it, val *pval) return 1; } + /* See comment in seq_iter_get_oop */ + if (iter) { val iter_item_meth = get_special_required_slot(iter, iter_item_m); it->ul.next = *pval = funcall1(iter_item_meth, iter); |