3 oneof untainted, tainted, untainted
7 parameter ==> untainted
9 tainted reference ==> tainted
10 untainted reference ==> untainted
11 maybetainted reference ==> blue
13 tainted + * ==> tainted
14 tainted + junky ==> error "Splat!"
16 tainted as untainted ==> error "Possibly tainted storage used as untainted."
17 tainted as tainted ==> tainted
18 untainted as tainted ==> peach
19 untainted as untainted ==> untainted