Regression: new function in module sometimes treated as imported with using

[toivoh]

In Julia 0.4, the code

module Test
    mod1{T}(x::T) = x < 1 ? x : mod1(x-1)
end

works and defines a module with a new function mod1. But with Julia master, I get instead the error message

ERROR: error in method definition: function Base.mod1 must be explicitly imported to be extended
 in eval(::Module, ::Any) at ./boot.jl:267

It seems that by using mod1 in the function body, Base.mod1 is considered to be imported before the function definition takes effect. If I make it non-recursive, remove the type parameter, or add a simple definition of mod1 in the Test module before the one given above, the error goes away.