[petsc-users] fieldsplit doesn't pass prefix to inner ksp

[anton]

Create preconditioner:

PCCreate(PETSC_COMM_WORLD, &pc);
PCSetOptionsPrefix(pc, "bf_");
PCSetFromOptions(pc);

Define fieldsplit options:

-bf_pc_type fieldsplit
-bf_pc_fieldsplit_type SCHUR
-bf_pc_fieldsplit_schur_factorization_type UPPER

Works OK.

Set options for the first field solver:

-bf_fieldsplit_0_ksp_type preonly
-bf_fieldsplit_0_pc_type lu

Doesn't work (ignored), because "bf_" prefix isn't pass to inner solver 
ksp (checked in the debugger).

Indeed, the following works:

-fieldsplit_0_ksp_type preonly
-fieldsplit_0_pc_type lu

Observed with 3.5 but not with 3.4

Thanks.
Anton