Intermittent compilertriltest exception on RISC-V

```
08:44:56  28: [0;32m[----------] [m19 tests from LinkageTest/3, where TypeParam = double
08:44:56  28/29 Test #28: comptest ..........................***Exception: Illegal 19.46 sec
```

Seen intermittently on RISC-V when running comptriltests.  Not reproducible when re-run.