[Routing] fix BC
bug #12397 [Routing] fix BC (nicolas-grekas)

This PR was merged into the 2.5 branch.

Discussion
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[Routing] fix BC

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | -
| License       | MIT
| Doc PR        | -

Tests on master and 2.5 are failing because this patch is missing.

Commits
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86e667b [Routing] fix BC