Fix memory leaks of ``Array`` objects detected by ASan.

Some of these leaks were introduced by the factory constructor for Array
objects (f049ff3bc04daead8c3bb9f06e89e71e2054c82a) but a few others have
been around for far longer.

This leak was fixed by introducing a ``ArrayCache`` object which has two
purposes

* Retains ownership of all created ``Array`` objects and destroys them when
  the ``ArrayCache`` destructor is called.
* Mimic the caching behaviour for symbolic arrays that was introduced
  by f049ff3bc04daead8c3bb9f06e89e71e2054c82a where arrays with the same
  name and size get "uniqued".

The Executor now maintains a ``arrayCache`` member that it uses and
passes by pointer to objects that need to construct ``Array`` objects (i.e.
``ObjectState``). This way when the Executor is destroyed all the
``Array`` objects get freed which seems like the right time to do this.

For Kleaver the ``ParserImpl`` has a ``TheArrayCache`` member that is
used for building ``Array`` objects. This means that the Parser must
live as long as the built expressions will be used otherwise we will
have a use after free. I'm not sure this is the right design choice.
It might be better to transfer ownership of the ``Array`` objects to
the root ``Decl`` returned by the parser.

1 files changed, 2 insertions, 0 deletions

diff --git a/lib/Core/Memory.h b/lib/Core/Memory.h
index 637f8772..d08bfb0c 100644
--- a/lib/Core/Memory.h
+++ b/lib/Core/Memory.h
@@ -27,6 +27,7 @@ namespace klee {
 class BitArray;
 class MemoryManager;
 class Solver;
+class ArrayCache;
 
 class MemoryObject {
   friend class STPBuilder;
@@ -234,6 +235,7 @@ private:
   void setKnownSymbolic(unsigned offset, Expr *value);
 
   void print();
+  ArrayCache *getArrayCache() const;
 };
   
 } // End klee namespace