Missed change for ptr in move constructor

Author: EricaCMitchell

src/TiledArray/tensor/tensor.h

@@ -233,7 +233,14 @@ class Tensor {
       : range_(std::move(range)), nbatch_(nbatch) {
     size_t size = range_.volume() * nbatch;
     allocator_type allocator;
+#if EIGEN_HAS_MAJOR_VERSION_5
+    // Eigen >=3.5.0 returns nullptr if size=0
+    auto* ptr = (!size && range_.rank())
+                    ? static_cast<pointer>(std::malloc(size))
+                    : allocator.allocate(size);
+#else
     auto* ptr = allocator.allocate(size);
+#endif
     // default construct elements of data only if can have any effect ...
     if constexpr (!std::is_trivially_default_constructible_v<T>) {
       // .. and requested