type piracy of diagm

[stevengj]

This method is type piracy:

ChainRulesCore.jl/src/tangent_types/thunks.jl

Lines 65 to 67 in 486922d

	function LinearAlgebra.diagm(m, n, kv::Pair{<:Integer,<:AbstractThunk}...)
	return diagm(m, n, (k => unthunk(v) for (k, v) in kv)...)
	end

In particular, it is inadvertently adding a fallback diagm(m::Any, n::Any) definition. e.g. this leads to odd error messages as in this discourse thread.

[stevengj]

I think you only want this method when at least one argument has an AbstractThunk, i.e.

function LinearAlgebra.diagm(m, n, kv::Pair{<:Integer,<:AbstractThunk}, kvs::Pair{<:Integer,<:AbstractThunk}...) 
     return diagm(m, n, (k => unthunk(v) for (k, v) in (kv, kvs...))...) 
 end 

[oxinabox]

Correct, I will fix this presently.
A motivating case of JuliaLang/julia#42222