Fix an issue with asynchronous execution in dpnp.fft module (#2067) (#2070)

* get the final list of dependent events just before using it

* update changelog.md

Author: vtavana

CHANGELOG.md

@@ -114,8 +114,8 @@ In addition, this release completes implementation of `dpnp.fft` module and adds
 * Resolved an issue with input array of `usm_ndarray` passed into `dpnp.ix_` [#2047](https://github.com/IntelPython/dpnp/pull/2047)
 * Added a workaround to prevent crash in tests on Windows in internal CI/CD (when running on either Lunar Lake or Arrow Lake) [#2062](https://github.com/IntelPython/dpnp/pull/2062)
 * Fixed a crash in `dpnp.choose` caused by missing control of releasing temporary allocated device memory [#2063](https://github.com/IntelPython/dpnp/pull/2063)
-* Resolve compilation warning and error while building in debug mode [#2066](https://github.com/IntelPython/dpnp/pull/2066)
-
+* Resolved compilation warning and error while building in debug mode [#2066](https://github.com/IntelPython/dpnp/pull/2066)
+* Fixed an issue with asynchronous execution in `dpnp.fft` module [#2067](https://github.com/IntelPython/dpnp/pull/2067)
 
 ## [0.15.0] - 05/25/2024
 

dpnp/fft/dpnp_utils_fft.py

@@ -264,6 +264,8 @@ def _copy_array(x, complex_input):
     dtype = x.dtype
     if numpy.min(x.strides) < 0:
         # negative stride is not allowed in OneMKL FFT
+        # TODO: support for negative strides will be added in the future
+        # versions of OneMKL, see discussion in MKLD-17597
         copy_flag = True
     elif complex_input and not dpnp.issubdtype(dtype, dpnp.complexfloating):
         # c2c/c2r FFT, if input is not complex, convert to complex
@@ -443,8 +445,6 @@ def _truncate_or_pad(a, shape, axes):
         else:
             # zero-padding
             exec_q = a.sycl_queue
-            _manager = dpu.SequentialOrderManager[exec_q]
-            dep_evs = _manager.submitted_events
             index[axis] = slice(0, a_shape[axis])  # orig shape
             a_shape[axis] = s  # modified shape
             order = "F" if a.flags.fnc else "C"
@@ -455,6 +455,8 @@ def _truncate_or_pad(a, shape, axes):
                 usm_type=a.usm_type,
                 sycl_queue=exec_q,
             )
+            _manager = dpu.SequentialOrderManager[exec_q]
+            dep_evs = _manager.submitted_events
             ht_copy_ev, copy_ev = ti._copy_usm_ndarray_into_usm_ndarray(
                 src=dpnp.get_usm_ndarray(a),
                 dst=z.get_array()[tuple(index)],