Testing segfaults on non-linux architectures

Following the recent introduction of `globjects` to Debian, packages have been built for various architectures. The status of the builds is summarized [here](https://buildd.debian.org/status/logs.php?pkg=globjects&ver=0.5.0-1).

I am wondering why testing for GNU Hurd and kFreeBSD fails, whilst succeeding for their x86 counterparts. Is there anything fundamentally non-portable in the `globjects` codebase?

Here is the relevant part of the log:
```
cd /«PKGBUILDDIR»/obj-x86_64-kfreebsd-gnu/source/tests && ../../globjects-test --gtest_output=xml:gtests-globjects-test.xml
[==========] Running 10 tests from 3 test cases.
[----------] Global test environment set-up.
[----------] 4 tests from ref_ptr_test
[ RUN ] ref_ptr_test.DeletesItsReferenced
Segmentation fault
```