[m-rev.] for post-commit review: fix many test failures in warnings

[Zoltan Somogyi]

For review by anyone.

Zoltan.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: Log.oa
Type: application/octet-stream
Size: 360 bytes
Desc: not available
URL: <http://lists.mercurylang.org/archives/reviews/attachments/20250913/506de04b/attachment.obj>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: DIFF.oa
Type: application/octet-stream
Size: 3573 bytes
Desc: not available
URL: <http://lists.mercurylang.org/archives/reviews/attachments/20250913/506de04b/attachment-0001.obj>