[BUG]: `register()` accepts a mismatched UUID under `python -O`

[fedonman]

Is this a duplicate?

• I confirmed there appear to be no duplicate issues for this bug and that I agree to the Code of Conduct

Type of Bug

Silent Failure

Component

cuda.core

Describe the bug

DeviceMemoryResource.register() and PinnedMemoryResource.register() check that the UUID they are given matches the resource's own with a bare assert in MP_register, so the check is absent whenever CPython runs with -O. The call then registers the resource under the other key and rewrites the resource's UUID, and mr.uuid reports the new value from then on.

How to Reproduce

import uuid
from cuda.core import Device, DeviceMemoryResource, DeviceMemoryResourceOptions
dev = Device(); dev.set_current()
mr = DeviceMemoryResource(dev, DeviceMemoryResourceOptions(ipc_enabled=True))
try:
    mr.register(uuid.UUID("00000000-0000-0000-0000-000000000001"))
except AssertionError:
    print("rejected")
else:
    print("accepted, uuid is now", mr.uuid)

$ python  repro.py
rejected
$ python -O repro.py
accepted, uuid is now 00000000-0000-0000-0000-000000000001

Expected behavior

register() should reject a UUID that is not the resource's own whether or not CPython was started with -O. Assertions are removed under -O, so the check as written does not exist in an optimized interpreter and the resource silently takes on the other key instead of raising.

Operating System

Ubuntu 26.04 LTS

nvidia-smi output

Tue Aug 25 15:01:31 2026       
+-----------------------------------------------------------------------------------------+
| NVIDIA-SMI 595.84                 Driver Version: 595.84         CUDA Version: 13.2     |
+-----------------------------------------+------------------------+----------------------+
| GPU  Name                 Persistence-M | Bus-Id          Disp.A | Volatile Uncorr. ECC |
| Fan  Temp   Perf          Pwr:Usage/Cap |           Memory-Usage | GPU-Util  Compute M. |
|                                         |                        |               MIG M. |
|=========================================+========================+======================|
|   0  NVIDIA GeForce RTX 3050 ...    Off |   00000000:01:00.0 Off |                  N/A |
| N/A   59C    P3            749W /   30W |      11MiB /   4096MiB |      8%      Default |
|                                         |                        |                  N/A |
+-----------------------------------------+------------------------+----------------------+