implement missing error

zokrates_core/src/flat_absy/mod.rs

@@ -42,13 +42,14 @@ pub enum RuntimeError {
     Division,
     Source,
     ArgumentBitness,
+    SelectRangeCheck,
 }
 
 impl RuntimeError {
     fn is_malicious(&self) -> bool {
         use RuntimeError::*;
 
-        !matches!(self, Source | Inverse | LtSum)
+        !matches!(self, Source | Inverse | LtSum | SelectRangeCheck)
     }
 }
 
@@ -79,6 +80,7 @@ impl fmt::Display for RuntimeError {
             Division => "Division check failed",
             Source => "User assertion failed",
             ArgumentBitness => "Argument bitness check failed",
+            SelectRangeCheck => "Out of bounds array access",
         };
 
         write!(f, "{}", msg)?;

zokrates_core/src/flatten/mod.rs

@@ -2053,6 +2053,7 @@ impl<'ast, T: Field> Flattener<'ast, T> {
         statements_flattened.push(FlatStatement::Condition(
             range_check,
             FlatExpression::Number(T::one()),
+            RuntimeError::SelectRangeCheck,
         ));
         FlatUExpression::with_field(result)
     }

zokrates_core/src/ir/smtlib2.rs

@@ -84,7 +84,7 @@ fn format_prefix_op_smtlib2<T: SMTLib2, Ts: SMTLib2>(
 impl<T: Field> SMTLib2 for Statement<T> {
     fn to_smtlib2(&self, f: &mut fmt::Formatter) -> fmt::Result {
         match *self {
-            Statement::Constraint(ref quad, ref lin) => {
+            Statement::Constraint(ref quad, ref lin, _) => {
                 write!(f, "(= (mod ")?;
                 quad.to_smtlib2(f)?;
                 write!(f, " |~prime|) (mod ")?;

zokrates_core/src/ir/visitor.rs

@@ -40,6 +40,10 @@ pub trait Visitor<T: Field>: Sized {
     fn visit_directive(&mut self, d: &Directive<T>) {
         visit_directive(self, d)
     }
+
+    fn visit_runtime_error(&mut self, e: &RuntimeError) {
+        visit_runtime_error(self, e)
+    }
 }
 
 pub fn visit_module<T: Field, F: Visitor<T>>(f: &mut F, p: &Prog<T>) {
@@ -48,9 +52,10 @@ pub fn visit_module<T: Field, F: Visitor<T>>(f: &mut F, p: &Prog<T>) {
 
 pub fn visit_statement<T: Field, F: Visitor<T>>(f: &mut F, s: &Statement<T>) {
     match s {
-        Statement::Constraint(quad, lin) => {
+        Statement::Constraint(quad, lin, error) => {
             f.visit_quadratic_combination(quad);
             f.visit_linear_combination(lin);
+            error.as_ref().map(|error| f.visit_runtime_error(error));
         }
         Statement::Directive(dir) => f.visit_directive(dir),
     }
@@ -96,3 +101,5 @@ pub fn visit_argument<T: Field, F: Visitor<T>>(f: &mut F, a: &FlatVariable) {
 pub fn visit_variable<T: Field, F: Visitor<T>>(_f: &mut F, _v: &FlatVariable) {}
 
 pub fn visit_value<T: Field, F: Visitor<T>>(_f: &mut F, _v: &T) {}
+
+fn visit_runtime_error<T: Field, F: Visitor<T>>(_f: &mut F, _: &RuntimeError) {}