Requested feature: With the fix to #1841 the compiler will be able to handle multiple harnesses with stubs, but it will rerun the Rust compiler multiple times independent on the set of stubs used on each harness.
Use case: Users may use the same stubs for a set of harnesses, and they can all be processed in the same compiler session. This will reduce the duplicated warnings emitted by the compiler, as well as the time compiling a crate with multiple harnesses that use the same stubs.
Link to relevant documentation (Rust reference, Nomicon, RFC):