[Lemon-devel] Memory corruption when using IterableValueMap on Class derived from lemon Graph

[Bernhard Kausler]

Dear all,

unfortunately, the user registration on the lemon website is broken and
I can't use the ticket system. Therefore, I report a bug here.

The following code causes a memory access error.
- Tested for lemon 1.2.1 and the latest lemon-main sources
- Doesn't happen for other graph maps like IdMap

---------- code begin ---------
#include <lemon/list_graph.h>
#include <lemon/maps.h>

using namespace lemon;

class MyGraph : public ListDigraph {
};

int main() {
  MyGraph derived;
  IterableValueMap<MyGraph, MyGraph::Node, int> derived_m2(derived);

  derived.addNode();

  return 0;
}
---------- code end -----------

gdb backtrace:
#0  0x00000000004059a3 in lemon::IterableValueMap<MyGraph,
lemon::ListDigraphBase::Node, int>::unlace (this=0x7fffffffdcf0,
key=...) at lemon-main/lemon/maps.h:3098
#1  0x0000000000405050 in lemon::IterableValueMap<MyGraph,
lemon::ListDigraphBase::Node, int>::add (this=0x7fffffffdcf0, key=...)
at lemon-main/lemon/maps.h:3255
#2  0x00000000004026ab in
lemon::AlterationNotifier<lemon::DigraphExtender<lemon::ListDigraphBase>, lemon::ListDigraphBase::Node>::add
(this=0x7fffffffdcc0, item=...) at
/home/bkausler/loca/include/lemon/bits/alteration_notifier.h:356
#3  0x00000000004018a7 in
lemon::DigraphExtender<lemon::ListDigraphBase>::addNode
(this=0x7fffffffdc80) at
/home/bkausler/local/include/lemon/bits/graph_extender.h:269
#4  0x00000000004012c8 in lemon::ListDigraph::addNode
(this=0x7fffffffdc80) at lemon-main/lemon/list_graph.h:352
#5  0x0000000000400f54 in main () at inheritance-bug.cpp:15

Best,
Bernhard Kausler