[Coin-lpsolver] Repeat calls to ClpInterior::primalDual()

[Mikhail Nediak]

Hi,

I am using a stable release of Clp and wondering about the behavior of
ClpInterior under repeat calls to primalDual() after problem data
modification. Specifically, I have the following questions:

* Is an instance of ClpInterior class intended to be reused in this way?

* If it is, are there any methods to be called in addition to modifying
the problem followed by primalDual()?

* With debug enabled, a repeat call to primalDual() causes an
invalid assertion in line 631 of ClpInterior.cpp
  assert (!deltaZ_);
inside createWorkingData() method. This is not surprising since 
deltaZ_ is not deallocated in deleteWorkingData() method, in contrast
to, say, deltaX_. Is this a feature or a bug?

Thanks in advance.

Best,
Mikhail