[BUG] some tests segfault sporadically on OSX

**Describe the bug**

**System**
Which OS, compiler, and compiler version are you using:
- OS: OSX (bigsur)
- Compiler and version: Apple Clang 13.0.0

**To reproduce**
1. at HEAD
2. cmake --build "build" --config Debug
3. cmake -E chdir "build" ctest ---build-config Debug

**Expected behavior**
All tests should pass at HEAD

**Actual behavior**
The following tests FAILED:
47 - register_benchmark_test (SEGFAULT)
59 - user_counters_tabular_test (SEGFAULT)

Keep re-running the tests (step 3), one or both of them could pass occasionally. There seems to be some level of indeterminism here but I haven't been able to track down.