Add empty recarray test, check for calloc fail

example/example20.py

@@ -17,3 +17,8 @@ arr = create_rec_simple(3)
 assert arr.dtype == dtype
 check_eq(arr, [(False, 0, 0.0), (True, 1, 1.5), (False, 2, 3.0)], dtype)
 check_eq(arr, [(False, 0, 0.0), (True, 1, 1.5), (False, 2, 3.0)], base_dtype)
+
+arr = create_rec_simple(0)
+assert arr.dtype == dtype
+check_eq(arr, [], dtype)
+check_eq(arr, [], base_dtype)

include/pybind11/numpy.h

@@ -116,6 +116,8 @@ public:
         auto buf_info = info;
         if (!buf_info.ptr)
             buf_info.ptr = std::calloc(info.size, info.itemsize);
+        if (!buf_info.ptr)
+            pybind11_fail("NumPy: failed to allocate memory for buffer");
         auto view = py::memoryview(buf_info);
 
         API& api = lookup_api();