From e1be00f06d8937f876b0163fa9c047a50f823855 Mon Sep 17 00:00:00 2001
From: Akosh Farkash <aakoshh@gmail.com>
Date: Tue, 14 Oct 2025 13:58:02 +0100
Subject: [PATCH 1/3] Add integration test

---
 .../execution_success/regression_10180/Nargo.toml    |  6 ++++++
 .../execution_success/regression_10180/Prover.toml   |  2 ++
 .../execution_success/regression_10180/src/main.nr   | 12 ++++++++++++
 3 files changed, 20 insertions(+)
 create mode 100644 test_programs/execution_success/regression_10180/Nargo.toml
 create mode 100644 test_programs/execution_success/regression_10180/Prover.toml
 create mode 100644 test_programs/execution_success/regression_10180/src/main.nr

diff --git a/test_programs/execution_success/regression_10180/Nargo.toml b/test_programs/execution_success/regression_10180/Nargo.toml
new file mode 100644
index 00000000000..7b68c0c84d4
--- /dev/null
+++ b/test_programs/execution_success/regression_10180/Nargo.toml
@@ -0,0 +1,6 @@
+[package]
+name = "regression_10180"
+type = "bin"
+authors = [""]
+
+[dependencies]
\ No newline at end of file
diff --git a/test_programs/execution_success/regression_10180/Prover.toml b/test_programs/execution_success/regression_10180/Prover.toml
new file mode 100644
index 00000000000..f0c44d10ce0
--- /dev/null
+++ b/test_programs/execution_success/regression_10180/Prover.toml
@@ -0,0 +1,2 @@
+b = true
+return = 193432430920915057603408161267722629873
diff --git a/test_programs/execution_success/regression_10180/src/main.nr b/test_programs/execution_success/regression_10180/src/main.nr
new file mode 100644
index 00000000000..f2dc1124857
--- /dev/null
+++ b/test_programs/execution_success/regression_10180/src/main.nr
@@ -0,0 +1,12 @@
+global G_B: [(str<2>, Field)] = &[
+    ("SM", 193432430920915057603408161267722629873),
+    ("QK", 28517051330822917784420357897851281178),
+    ("XJ", -303354957477210748157621923488550325890),
+];
+fn main(b: bool) -> pub Field {
+    if b {
+        G_B[(1783103175_u32 % G_B.len())].1
+    } else {
+        (G_B[1771627614_u32].1 / G_B[2334904280_u32].1)
+    }
+}

From 89f883a620e20e7f1e8097f7135ac992d3c19d25 Mon Sep 17 00:00:00 2001
From: Akosh Farkash <aakoshh@gmail.com>
Date: Tue, 14 Oct 2025 13:58:22 +0100
Subject: [PATCH 2/3] Do not return IndexOutOfBounds on overflow if side
 effects are disabled

---
 .../src/ssa/interpreter/mod.rs                | 25 +++++++++++++++----
 1 file changed, 20 insertions(+), 5 deletions(-)

diff --git a/compiler/noirc_evaluator/src/ssa/interpreter/mod.rs b/compiler/noirc_evaluator/src/ssa/interpreter/mod.rs
index 2b09a14c98f..6727fb69d40 100644
--- a/compiler/noirc_evaluator/src/ssa/interpreter/mod.rs
+++ b/compiler/noirc_evaluator/src/ssa/interpreter/mod.rs
@@ -964,13 +964,27 @@ impl<'ssa, W: Write> Interpreter<'ssa, W> {
         result: ValueId,
         side_effects_enabled: bool,
     ) -> IResult<()> {
+        // When there is a problem indexing the array, but side effects are disabled,
+        // define the value as uninitialized.
+        let uninitialized = |this: &mut Self| {
+            let typ = this.dfg().type_of_value(result);
+            let value = Value::uninitialized(&typ, result);
+            this.define(result, value)
+        };
+
         let offset = self.dfg().array_offset(array, index);
         let array = self.lookup_array_or_slice(array, "array get")?;
         let length = array.elements.borrow().len() as u32;
-        let index = self.lookup_array_index(index, "array get index", length)?;
+
+        let index = match self.lookup_array_index(index, "array get index", length) {
+            Err(InterpreterError::IndexOutOfBounds { .. }) if !side_effects_enabled => {
+                return uninitialized(self);
+            }
+            other => other?,
+        };
         let mut index = index - offset.to_u32();
 
-        let element = if length == 0 {
+        if length == 0 {
             // Accessing an array of 0-len is replaced by asserting
             // the branch is not-taken during acir-gen and
             // a zeroed type is used in case of array get
@@ -978,10 +992,11 @@ impl<'ssa, W: Write> Interpreter<'ssa, W> {
             if side_effects_enabled {
                 return Err(InterpreterError::IndexOutOfBounds { index: index.into(), length });
             } else {
-                let typ = self.dfg().type_of_value(result);
-                Value::uninitialized(&typ, result)
+                return uninitialized(self);
             }
-        } else {
+        }
+
+        let element = {
             // An array_get with false side_effects_enabled is replaced
             // by a load at a valid index during acir-gen.
             if !side_effects_enabled {

From 5a1dc6e860518871d9957fea66208002dd0222f0 Mon Sep 17 00:00:00 2001
From: Akosh Farkash <aakoshh@gmail.com>
Date: Tue, 14 Oct 2025 14:05:47 +0100
Subject: [PATCH 3/3] Add insta

---
 .../regression_10180/Prover.toml                |  2 +-
 .../execute__tests__expanded.snap               | 17 +++++++++++++++++
 .../execute__tests__stdout.snap                 |  5 +++++
 3 files changed, 23 insertions(+), 1 deletion(-)
 create mode 100644 tooling/nargo_cli/tests/snapshots/execution_success/regression_10180/execute__tests__expanded.snap
 create mode 100644 tooling/nargo_cli/tests/snapshots/execution_success/regression_10180/execute__tests__stdout.snap

diff --git a/test_programs/execution_success/regression_10180/Prover.toml b/test_programs/execution_success/regression_10180/Prover.toml
index f0c44d10ce0..458d4bce321 100644
--- a/test_programs/execution_success/regression_10180/Prover.toml
+++ b/test_programs/execution_success/regression_10180/Prover.toml
@@ -1,2 +1,2 @@
 b = true
-return = 193432430920915057603408161267722629873
+return = "193432430920915057603408161267722629873"
diff --git a/tooling/nargo_cli/tests/snapshots/execution_success/regression_10180/execute__tests__expanded.snap b/tooling/nargo_cli/tests/snapshots/execution_success/regression_10180/execute__tests__expanded.snap
new file mode 100644
index 00000000000..275259d9154
--- /dev/null
+++ b/tooling/nargo_cli/tests/snapshots/execution_success/regression_10180/execute__tests__expanded.snap
@@ -0,0 +1,17 @@
+---
+source: tooling/nargo_cli/tests/execute.rs
+expression: expanded_code
+---
+global G_B: [(str<2>, Field)] = &[
+    ("SM", 193432430920915057603408161267722629873),
+    ("QK", 28517051330822917784420357897851281178),
+    ("XJ", -303354957477210748157621923488550325890),
+];
+
+fn main(b: bool) -> pub Field {
+    if b {
+        G_B[1783103175_u32 % G_B.len()].1
+    } else {
+        G_B[1771627614_u32].1 / G_B[2334904280_u32].1
+    }
+}
diff --git a/tooling/nargo_cli/tests/snapshots/execution_success/regression_10180/execute__tests__stdout.snap b/tooling/nargo_cli/tests/snapshots/execution_success/regression_10180/execute__tests__stdout.snap
new file mode 100644
index 00000000000..a289120c7a6
--- /dev/null
+++ b/tooling/nargo_cli/tests/snapshots/execution_success/regression_10180/execute__tests__stdout.snap
@@ -0,0 +1,5 @@
+---
+source: tooling/nargo_cli/tests/execute.rs
+expression: stdout
+---
+[regression_10180] Circuit output: 0x9185bb28e2cfba7cb4079a5c3ada32f1