diff --git a/storage-proofs/post/src/fallback/vanilla.rs b/storage-proofs/post/src/fallback/vanilla.rs
index 3810f48db..e453f8d3e 100644
--- a/storage-proofs/post/src/fallback/vanilla.rs
+++ b/storage-proofs/post/src/fallback/vanilla.rs
@@ -506,7 +506,7 @@ impl<'a, Tree: 'a + MerkleTreeTrait> ProofScheme<'a> for FallbackPoSt<'a, Tree>
                     &comm_r_last,
                 )) != AsRef::<[u8]>::as_ref(comm_r)
                 {
-                    error!("comm_c != comm_r_last: {:?}", sector_id);
+                    error!("hash(comm_c || comm_r_last) != comm_r: {:?}", sector_id);
                     return Ok(false);
                 }