The catch unit-testing framework includes the C standard library's printf-family functions; consequently, it clashes with our library when we alias the standard printf-family function names. In the past this was circumvented by including printf.c within a namespace, but now that printf.c is more language-aware, that's not possible; plus, it wasn't a good idea, since it was testing something others than what library users will actually be doing.

Anyway, now we have this clash. This means either we need to not run the test suite with the aliased names, or ... do something else?