Handle zeros even better

Author: kshyatt

src/implementations/svd.jl

@@ -189,6 +189,12 @@ end
 
 function svd_vals!(A::AbstractMatrix, S, alg::LAPACK_SVDAlgorithm)
     check_input(svd_vals!, A, S, alg)
+    m, n = size(A)
+    minmn = min(m, n)
+    if minmn == 0
+        zero!(S)
+        return S
+    end
     U, Vᴴ = similar(A, (0, 0)), similar(A, (0, 0))
 
     alg_kwargs = Base.structdiff(alg.kwargs, NamedTuple{(:fixgauge,)})
@@ -447,6 +453,12 @@ _largest(x, y) = abs(x) < abs(y) ? y : x
 
 function svd_vals!(A::AbstractMatrix, S, alg::GPU_SVDAlgorithm)
     check_input(svd_vals!, A, S, alg)
+    m, n = size(A)
+    minmn = min(m, n)
+    if minmn == 0
+        zero!(S)
+        return S
+    end
     U, Vᴴ = similar(A, (0, 0)), similar(A, (0, 0))
 
     alg_kwargs = Base.structdiff(alg.kwargs, NamedTuple{(:fixgauge,)})