Crash when running end-to-end tests with simple switch

[fruffy]

When doing end-to-end tests I have observed strange crashes with simple switch.
I run the following command
python p4_tv/p4c/backends/bmv2/run-bmv2-test.py p4_tv/p4c -v -b -bd p4c/build/ p4_tv/bugs/simple_switch/two_bools.p4

and I get this output:

Writing temporary files into  ./tmp1xr6wjtr                                        
Executing  p4c/build//p4c-bm2-ss -o ./tmp1xr6wjtr/two_bools.json p4_tv/bugs/simple_switch/two_bools.p4
Exit code  0
Check for  p4_tv/bugs/simple_switch/two_bools.stf
Running model
Running behavioral-model/targets/simple_switch/simple_switch --log-file switch.log --log-flush --use-files 0 --thrift-port 9972 --device-id 882 -i 0@pcap0 .././tmp1xr6wjtr/two_bools.json
Calling target program-options parser
Invalid 'type' in expression: ''
bad json:
{
   "left" : null,
   "op" : "d2b",
   "right" : {
      "type" : "field",
      "value" : [ "scalars", "tmp_0" ]
   }
}

*** Test failed

It looks like this might be a problem in the P4C BMV2 back-end and not the behavioral model?
I have two examples, they look related to me:

two_bools.p4.txt
two_bools.stf.txt
two_bools_2.stf.txt
two_bools_2.p4.txt