CAIN-42 CAIN StudioCFVE · Module 2 of 5 · 13 min
Compiling code into logic
To verify code, translate it into the solver's language: variables become symbolic values, branches become conditional constraints, loops are bounded or summarised.
CAIN's VeriCoding gate compiles a Python subset into Z3 expressions. Unsupported constructs are rejected rather than approximated, so the gate fails closed.
Bounded verification is honest only if the bound is stated: 'no overflow for loops up to 16 iterations' is not 'no overflow'.
Key points
- Symbolic values, conditional constraints, bounded loops.
- Reject unsupported constructs.
- State the bounds.
In the CAIN-42 codebase
vericoding-gate/expr_compiler.py— Python-subset → Z3 compiler
Practice check
Practice 1 · choose one
An unsupported construct in VeriCoding is…
Practice 2 · true or false