<div id="_htmlarea_default_style_" style="font:10pt arial,helvetica,sans-serif">Dear PETSc devs,<br><br>I am getting the following error with
petsc-3.5.1:<br><br>[0]PETSC ERROR: --------------------- Error Message --------------------------------------------------------------<br>[0]PETSC
ERROR: Null argument, when expecting valid pointer<br>[0]PETSC ERROR: Null Object: Parameter # 1<br>[0]PETSC ERROR: See
http://www.mcs.anl.gov/petsc/documentation/faq.html for trouble shooting.<br>[0]PETSC ERROR: Petsc Release Version 3.5.1, Jul, 24, 2014<br>[0]PETSC
ERROR: /build/main on a openmpi-gcc-double-debug-c-shared named e1334 by ag Mon Aug 11 18:42:07 2014<br>[0]PETSC ERROR: Configure options
--with-petsc-arch=openmpi-gcc-double-debug-c-shared --with-x=0 --download-mumps --download-metis --download-scalapack --download-blacs
--with-scalar-type=real --download-blas-lapack --with-precision=double --download-parmetis --with-shared-libraries=1 --with-debugging=1
--with-hypre-dir=/lib/hypre-2.9.1a --download-fblaslapack=1<br>[0]PETSC ERROR: #1 PetscObjectStateGet() line 38 in
/lib/petsc-3.5.1/src/sys/objects/state.c<br>[0]PETSC ERROR: #2 PCSetUp() line 875 in /lib/petsc-3.5.1/src/ksp/pc/interface/precon.c<br>[0]PETSC ERROR:
#3 KSPSetUp() line 305 in /lib/petsc-3.5.1/src/ksp/ksp/interface/itfunc.c<br>[0]PETSC ERROR: #4 KSPSolve() line 417 in
/lib/petsc-3.5.1/src/ksp/ksp/interface/itfunc.c<br><br>I have used LSQR here which was setup in the following way:<br><br> 
KSPCreate(communicator, &ksp);<br>  KSPSetType(ksp, KSPLSQR);<br>  KSPSetTolerances(ksp, tol, PETSC_DEFAULT, PETSC_DEFAULT,
max_iterations);<br>  KSPSetFromOptions(ksp);<br>  KSPGetPC(ksp, &pc);<br>  PCSetType(pc, PCNONE);<br>  KSPSetOperators(ksp,
A, PETSC_NULL);<br>  KSPSolve(ksp, b, x);<br><br>The code works fine with petsc-3.4.4 (provided that I pass DIFFERENT_NONZERO_PATTERN to the
KSPSetFromOptions). Any idea?<br><br>Regards,<br>Alexander<br></div>