  Whereas point-gap topological phases are responsible for exceptional
phenomena intrinsic to non-Hermitian systems, their realization in quantum
materials is still elusive. Here we propose a simple and universal platform of
point-gap topological phases constructed from Hermitian topological insulators
and superconductors. We show that (d-1)-dimensional point-gap topological
phases are realized by making a boundary in d-dimensional topological
insulators and superconductors dissipative. A crucial observation of the
proposal is that adding a decay constant to boundary modes in d-dimensional
topological insulators and superconductors is topologically equivalent to
attaching a (d-1)-dimensional point-gap topological phase to the boundary. We
furthermore establish the proposal from the extended version of the
Nielsen-Ninomiya theorem, relating dissipative gapless modes to point-gap
topological numbers. From the bulk-boundary correspondence of the point-gap
topological phases, the resultant point-gap topological phases exhibit
exceptional boundary states or in-gap higher-order non-Hermitian skin effects.
