Method definition overwritten warnings during bootstrap

[eschnett]

When bootstrapping Julia 0.5 (release branch) on ARM I see these warnings:

sort.jl
WARNING: Method definition searchsortedfirst(AbstractArray{T<:Any, 1}, Any) in module Sort at sort.jl:184 overwritten at sort.jl:187.
WARNING: Method definition searchsortedlast(AbstractArray{T<:Any, 1}, Any) in module Sort at sort.jl:184 overwritten at sort.jl:187.
WARNING: Method definition searchsorted(AbstractArray{T<:Any, 1}, Any) in module Sort at sort.jl:184 overwritten at sort.jl:187.

The respective method definitions

for s in [:searchsortedfirst, :searchsortedlast, :searchsorted]
    @eval begin
        $s(v::AbstractVector, x, o::Ordering) = $s(v,x,1,length(v),o)
        $s(v::AbstractVector, x;
           lt=isless, by=identity, rev::Bool=false, order::Ordering=Forward) =
            $s(v,x,ord(lt,by,rev,order))
        $s(v::AbstractVector, x) = $s(v, x, Forward)
    end
end

seem indeed conflicting -- they only differ by keyword arguments.

[yuyichao]

This is to workaround kw lowering inefficiency. Can be removed after the kw args are more efficient.

[eschnett]

Add a comment to the source explaining this?

Also, if both methods are accessible, then then warning isn't quite right.

[yuyichao]

KW argument affecting dispatch is #9498