3-argument `dot` errors for empty vectors

[matthias314]

Rewriting it as a 2-argument dot works fine:

julia> m = 0; n = 0; v = zeros(m); a = zeros(m, n); w = zeros(n); dot(v, a*w)
0.0

julia> dot(v, a, w)
ERROR: BoundsError: attempt to access 0-element Vector{Float64} at index [1]
[...]

julia> m = 1; n = 0; v = zeros(m); a = zeros(m, n); w = zeros(n); dot(v, a*w)
0.0

julia> dot(v, a, w)
ERROR: BoundsError: attempt to access 1×0 Matrix{Float64} at index [1]
[...]

julia> m = 0; n = 1; v = zeros(m); a = zeros(m, n); w = zeros(n); dot(v, a*w)
0.0

julia> dot(v, a, w)
ERROR: BoundsError: attempt to access 0-element Vector{Float64} at index [1]
[...]

Julia Version 1.12.1
Commit ba1e628ee49 (2025-10-17 13:02 UTC)
Build Info:
  Official https://julialang.org release