From 18ba49c694ab67bc3d7c7b112fecb8e9778f70af Mon Sep 17 00:00:00 2001
From: Folkert <folkert@folkertdev.nl>
Date: Fri, 22 Apr 2022 19:29:52 +0200
Subject: [PATCH] add comment

---
 compiler/can/src/reference_matrix.rs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/compiler/can/src/reference_matrix.rs b/compiler/can/src/reference_matrix.rs
index d0052993e4..7db76dfd26 100644
--- a/compiler/can/src/reference_matrix.rs
+++ b/compiler/can/src/reference_matrix.rs
@@ -104,6 +104,8 @@ impl ReferenceMatrix {
                         }
                     }
 
+                    // NOTE: we use -1 to mark nodes that have no predecessors, but are already
+                    // part of an earlier group. That ensures nodes are added to just 1 group
                     let count = preds_map[succ];
                     preds_map[succ] = -1;