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1 files changed, 3 insertions, 0 deletions

diff --git a/src/state.h b/src/state.h
index d7987ba..58fac13 100644
--- a/src/state.h
+++ b/src/state.h
@@ -71,6 +71,9 @@ struct Pool {
 
   /// |current_use_| is the total of the weights of the edges which are
   /// currently scheduled in the Plan (i.e. the edges in Plan::ready_).
+  /// This is generally <= to depth_. It can exceed it very briefly when the
+  /// pool is notified about an edge that's about to be finished that will
+  /// not actually be started. See Plan::NodeFinished().
   int current_use_;
   int depth_;