Fix for CID 1063852: Uninitialized scalar field (UNINIT_CTOR)

@camillescott @ctb or @luizirber please merge

This closes #313 

- [ ] Is it mergable
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- [ ] If it introduce new functionality in scripts/ is it tested?
  Check for code coverage.
- [ ] Is it well formatted? Look at `pep8`/`pylint`, `cppcheck`, and
  `make doc` output. Use `autopep8` and `astyle -A10` if needed.
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