False positive `used-before-assignment` when `else` of `try/else` calls `sys.exit()`

[kayhayen]

Bug description

Given this code snippet:

    try:
        yamllint.cli.run([document])
    except SystemExit as e:
        lint_result = e.code
    else:
        sys.exit("Error, yamllint didn't raise expected SystemExit exception.")
    if lint_result != 0:
        sys.exit("Error, no lint clean yaml.")

    my_print("OK.", style="blue")

Since sys.exit() in the else branch is aborting, there is no doubt that lint_result must be assigned.

Configuration

No configuration

Command used

pylint m.py

Pylint output

Warning used-before-assignment for the `lint_result` usage.

Expected behavior

Warning should not be given.

Pylint version

pylint 2.15.3
astroid 2.12.10
Python 3.9.2 (default, Feb 28 2021, 17:03:44)

OS / Environment

Debian Buster with PyPI packages

Additional dependencies

No response

[Pierre-Sassoulas]

The issue look similar to #7520.

[jacobtylerwalls]

Similar issue as #6790, because the patch (#6791) only handled return, not sys.exit.

Should be an easy patch for a contributor to extend #6791. Could consider moving BUILTIN_EXIT_FUNCS to a common constant file and then use that.