fill unstored block with zeros

Author: lkdvos

src/blocksparsearrayinterface/getunstoredblock.jl

@@ -32,7 +32,7 @@ function (f::GetUnstoredBlock)(
     return length(f.axes[d][Block(I[d])])
   end
   if I[1] == I[2]
-    diag = similar(V, b_size[1])
+    diag = zero!(similar(V, b_size[1]))
     return LinearAlgebra.Diagonal{T,V}(diag)
   else
     return zeros(T, b_size...)