Unfortunately, this has a lot of false positive, preventing me from adding it to my test suites.

But extremely useful â€“ I found a few!

But, this remains:

```
julia> using VectorizationBase, Test
[ Info: Precompiling VectorizationBase [3d5dd08c-fd9d-11e8-17fa-ed2836048c2f]
julia> detect_unbound_args(VectorizationBase)
[1] gep(ptr::Ptr{T}, i::Tuple{Vararg{VecElement{I},W}}) where {W, T, I<:Integer} in VectorizationBase at /home/chriselrod/.julia/dev/VectorizationBase/src/vectorizable.jl:202
[2] vbroadcast(::Type{Tuple{Vararg{VecElement{T},W}}}, ptr::Ptr) where {W, T} in VectorizationBase at /home/chriselrod/.julia/dev/VectorizationBase/src/VectorizationBase.jl:140
[3] vbroadcast(::Type{Tuple{Vararg{VecElement{T},W}}}, v::Tuple{Vararg{VecElement{T},W}}) where {W, T} in VectorizationBase at /home/chriselrod/.julia/dev/VectorizationBase/src/VectorizationBase.jl:142
[4] vbroadcast(::Type{Tuple{Vararg{VecElement{T1},W}}}, s::T2) where {W, T1<:Integer, T2<:Integer} in VectorizationBase at /home/chriselrod/.julia/dev/VectorizationBase/src/VectorizationBase.jl:139
[5] vzero(::Type{Tuple{Vararg{VecElement{T},W}}}) where {W, T} in VectorizationBase at /home/chriselrod/.julia/dev/VectorizationBase/src/VectorizationBase.jl:117
[6] vbroadcast(::Type{Tuple{Vararg{VecElement{T1},W}}}, s) where {W, T1} in VectorizationBase at /home/chriselrod/.julia/dev/VectorizationBase/src/VectorizationBase.jl:138
[7] vone(::Type{Tuple{Vararg{VecElement{T},W}}}) where {W, T} in VectorizationBase at /home/chriselrod/.julia/dev/VectorizationBase/src/VectorizationBase.jl:146
```

Lines 138-146, as an example:

```
@inline vbroadcast(::Type{Vec{W,T1}}, s) where {W,T1} = vbroadcast(Vec{W,T1}, convert(T1,s))
@inline vbroadcast(::Type{Vec{W,T1}}, s::T2) where {W,T1<:Integer,T2<:Integer} = vbroadcast(Vec{W,T1}, s % T1)
@inline vbroadcast(::Type{Vec{W,T}}, ptr::Ptr) where {W,T} = vbroadcast(Vec{W,T}, Base.unsafe_convert(Ptr{T},ptr))
@inline vbroadcast(::Type{SVec{W,T}}, s) where {W,T} = SVec(vbroadcast(Vec{W,T}, s))
@inline vbroadcast(::Type{Vec{W,T}}, v::Vec{W,T}) where {W,T} = v
@inline vbroadcast(::Type{SVec{W,T}}, v::SVec{W,T}) where {W,T} = v
@inline vbroadcast(::Type{SVec{W,T}}, v::Vec{W,T}) where {W,T} = SVec(v)
@inline vone(::Type{Vec{W,T}}) where {W,T} = vbroadcast(Vec{W,T}, one(T))
```

I really wish this were a parser error. Once upon a time it was rendering this issue harmless, but now it is rather nasty.