Question

I get a segmentation fault when iterating over a set.

The stack trace points to:

  0x000000081193ccc5 in std::_Rb_tree_increment (__x=0x1) at /libstdc++/src/tree.cc:68
  0x0000000806c3107e in std::_Rb_tree_const_iterator<test *>::operator++     at stl_tree.h:266

but I get nothing more informative but the last line of crash is as below.

The iterator is over a set.

 typedef std::set<test*,test_less> test_set_t;

 test_set_t& set(bt->getSet());   // getSet() will return reference to the class bt member variable set

 test_set_t::iterator pos = set.begin();

 test empty(val);
 test* last_ptr = &empty;

 for (; pos != set.end(); last_ptr = *pos++) {       // gdb shows this as last line

I cannot see the issue. Thanks in advance.

Answer 1

Most likely either the set is empty or you erased the item pos was pointing to while iterating.