message: Labeling one of the PetscParMatrix constructors as "explicit", see
diff: @@ -181,7 +181,7 @@ public:
  PETSc format @a tid. */
  /** The supported type ids are: Operator::PETSC_MATAIJ,
  Operator::PETSC_MATIS, and Operator::PETSC_MATSHELL. */
  - PetscParMatrix(const HypreParMatrix *ha,
  + explicit PetscParMatrix(const HypreParMatrix *ha,
  Operator::Type tid = Operator::PETSC_MATAIJ);
  /** @brief Convert an mfem::Operator into a PetscParMatrix in the given PETSc
  