stk_top          1038 ext/mbstring/oniguruma/regexec.c                           OnigStackType* stk_top, UChar* str, regex_t* reg)
stk_top          1044 ext/mbstring/oniguruma/regexec.c   while (k < stk_top) {
stk_top          1056 ext/mbstring/oniguruma/regexec.c         r = make_capture_history_tree(child, kp, stk_top, str, reg);