Hi,

I just realized that there may be a bug in UmfPackSupport:

the variable m_extractedDataAreDirty seems to be initialized (UmfPackSuppoert.h:365) only after it is used inside an if clause (UmfPackSuppoert.h:344).
It does not appear to be initialized anywhere else.

Am I looking at this right?

Best regards,
João Leal

P.S. - I've also realized that UmfPackLU factorization supports rectangular matrices, perhaps this could be in the documentation since it is the only sparse LU solver that does factorization of rectangular matrices.

Confirmed with valgrind!
Added a bug report:
http://eigen.tuxfamily.org/bz/show_bug.cgi?id=911

Fixed. See: http://eigen.tuxfamily.org/bz/show_bug.cgi?id=911