Run fixpoint per strongly connected component

Cargo.toml

@@ -22,7 +22,7 @@ intrusive-collections = "0.9.7"
 parking_lot = "0.12"
 portable-atomic = "1"
 rustc-hash = "2"
-smallvec = "1"
+smallvec = { version = "1", features = ["const_new"] }
 thin-vec = { version = "0.2.14" }
 tracing = { version = "0.1", default-features = false, features = ["std"] }
 

src/active_query.rs

@@ -498,7 +498,7 @@ impl fmt::Display for Backtrace {
             if full {
                 write!(fmt, " -> ({changed_at:?}, {durability:#?}")?;
                 if !cycle_heads.is_empty() || !iteration_count.is_initial() {
-                    write!(fmt, ", iteration = {iteration_count:?}")?;
+                    write!(fmt, ", iteration = {iteration_count}")?;
                 }
                 write!(fmt, ")")?;
             }
@@ -517,7 +517,7 @@ impl fmt::Display for Backtrace {
                         }
                         write!(
                             fmt,
-                            "{:?} -> {:?}",
+                            "{:?} -> iteration = {}",
                             head.database_key_index, head.iteration_count
                         )?;
                     }