diff --git a/hercules_opt/src/ccp.rs b/hercules_opt/src/ccp.rs
index 692d0f71d1229087d6a20514cc63f1a356f8f0b6..cf3a0919585b4254ff4d3f6996755c063bca68d6 100644
--- a/hercules_opt/src/ccp.rs
+++ b/hercules_opt/src/ccp.rs
@@ -845,11 +845,24 @@ fn ccp_flow_function(
         }
         Node::Read {
             collect,
-            indices: _,
-        } => CCPLattice {
-            reachability: inputs[collect.idx()].reachability.clone(),
-            constant: ConstantLattice::bottom(),
-        },
+            indices,
+        } => {
+            let mut reachability = inputs[collect.idx()].reachability.clone();
+            for index in indices.iter() {
+                if let Index::Position(positions) = index {
+                    for position in positions.iter() {
+                        reachability = ReachabilityLattice::join(
+                            &reachability,
+                            &inputs[position.idx()].reachability,
+                        );
+                    }
+                }
+            }
+            CCPLattice {
+                reachability,
+                constant: ConstantLattice::bottom(),
+            }
+        }
         // Projection handles reachability when following an if or match.
         Node::Projection { control, selection } => match &editor.func().nodes[control.idx()] {
             Node::If { control: _, cond } => {
diff --git a/juno_samples/nested_ccp/src/main.rs b/juno_samples/nested_ccp/src/main.rs
index 1acea9bfa9e6a68c797845294a5cdfc00046927a..f866112f34914add4f9598d217bf6589fd033dba 100644
--- a/juno_samples/nested_ccp/src/main.rs
+++ b/juno_samples/nested_ccp/src/main.rs
@@ -8,8 +8,9 @@ juno_build::juno!("nested_ccp");
 
 fn main() {
     async_std::task::block_on(async {
+        let mut a = vec![17.0, 18.0, 19.0];
         let output = unsafe {
-            ccp_example().await
+            ccp_example(a.as_mut_ptr()).await
         };
         println!("{}", output);
         assert_eq!(output, 1.0);
diff --git a/juno_samples/nested_ccp/src/nested_ccp.jn b/juno_samples/nested_ccp/src/nested_ccp.jn
index 506f0361f0792d45ebd0a6c8582335b7883562b4..7a9575854ee5220c67ffa3c4a784458646677119 100644
--- a/juno_samples/nested_ccp/src/nested_ccp.jn
+++ b/juno_samples/nested_ccp/src/nested_ccp.jn
@@ -1,15 +1,15 @@
 #[entry]
-fn ccp_example() -> f32 {
+fn ccp_example(arg : f32[3]) -> f32 {
   let x : f32 = 2;
   if x < 3 {
     x = 1;
   } else {
     if x == 1 {
-      x = 4;
+      x = 3;
     } else {
-      x = 1;
+      x = 7;
     }
   }
-  if false { for i = 0 to 3 by 1 { } }
+  if false { for i = 0 to 3 by 1 { x = arg[i]; arg[i] = 0; } }
   return x;
 }