Fix build on mach-based OS which are not OS X

The source branch has been detected as being protected. Various steps in this project's workflow require rewriting history (including, but not limited to, any code reformatting, commit squashing, and commit message clarifications). Your source branch has been automatically unprotected, but in the future, please try to use topic branches for development.

@sthibaul Thanks.

Do: test

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Branch-at-master: bb0d55c8

Do: merge

Errors:

• The name of the topic (master) is the same as a branch in the project. Use the --topic option to merge with a different name.

Do: merge --topic mach-fix

merged

mentioned in commit d50f49e5