Describe the bug

Current working directory is not restored when using _comp_compgen -C in some cases.

To reproduce

Using removepkg as an example because it uses _comp_compgen -C:

1. Run mkdir -p tmp/var/log/packages && touch tmp/var/log/packages/{foo,bar,baz} && cd tmp.
2. Run ROOT=$PWD (that's setup for removepkg).
3. Then try completing with a prefix that is not found, for example: removepkg a<TAB>.
4. After that, you can type Ctrl-U or Ctrl-C to clear the line.
5. Run pwd and see that your current working directory has changed to ./var/log/packages ($PWD hasn't changed).
6. To clean-up: cd "$ROOT"/.. && unset ROOT && rm -rf tmp

Expected behavior

After step 3, the shell's working directory should be the same as before.

Versions (please complete the following information)

• Operating system name/distribution and version: macOS 15.6.1
• bash version, echo "$BASH_VERSION": 5.3.3(1)-release
• bash-completion version, (IFS=.; echo "${BASH_COMPLETION_VERSINFO[*]}"): 2 16 0

Additional context

Debug trace

debug-trace.log