Unnamed return variable is displayed incorrectly in counter example

[lum7na]

Description

When the return value is unnamed, the left side of the equality sign in the counterexample appears empty.

contract C {
  function f(uint256 value) public payable returns(bool) {
    value = value / value;
  }
}

Compiled with solc --model-checker-engine all a.sol:

Warning: CHC: Division by zero happens here.
Counterexample:

value = 0
 = false // The left side of the equality sign here is empty.

Transaction trace:
C.constructor()
C.f(0){ msg.value: 19 }
 --> out.sol:3:13:
  |
3 |     value = value / value;
  |             ^^^^^^^^^^^^^

Environment

• Compiler version: 0.8.26