diff --git a/erfa/ufunc.c.templ b/erfa/ufunc.c.templ
index 8c6baec..9edddb3 100644
--- a/erfa/ufunc.c.templ
+++ b/erfa/ufunc.c.templ
@@ -219,6 +219,8 @@ static void ufunc_loop_{{ func.pyname }}(
    {#- /* if needed, allocate memory for contiguous eraLDBODY copies */ #}
    {%- if func.user_dtype == 'dt_eraLDBODY' %}
     if (copy_b) {
+        // Note that we can't use PyArray_malloc here as it is an alias to PyMem_RawMalloc
+        // which is not available in the Python limited API
         _b = malloc(nb * sizeof(eraLDBODY));
         if (_b == NULL) {
             PyErr_NoMemory();