PEP 765: What's New warnings filter suggestions

For CI use cases where static code analysis is in use,
emitting SyntaxWarnings is essentially redundant.

Accordingly, there's no harm in suggesting that folks
turn them off to avoid poor interactions between PEP 765
and treating warnings as errors.

Author: ncoghlan

Doc/whatsnew/3.14.rst

@@ -937,6 +937,19 @@ The compiler now emits a :exc:`SyntaxWarning` when a :keyword:`return`,
 leaving a :keyword:`finally` block.
 This change is specified in :pep:`765`.
 
+For use cases where this change is inconvenient (such as those where the
+warnings are redundant due to code linting), syntax warnings specifically
+may be switched off via the :ref:`warning filter <warning-filter>`, using the
+clause ``ignore::SyntaxWarning``. This can also be specified in combination
+with a filter that converts other warnings to errors (for example, passing
+``-Werror -Wignore::SyntaxWarning`` as CLI options, or setting
+``PYTHONWARNINGS=error,ignore::SyntaxWarning``).
+
+Note that applying such a filter at runtime (rather than via the interpreter's
+startup configuration) will only suppress the warning in code that is compiled
+*after* the filter is adjusted. Code that is compiled prior to the filter
+adjustment (for example, when a module is imported) will still emit the warning.
+
 (Contributed by Irit Katriel in :gh:`130080`.)