diff --git a/compiler/rustc_mir/src/dataflow/framework/graphviz.rs b/compiler/rustc_mir/src/dataflow/framework/graphviz.rs
index 179c471cf4829..94151fbd0903a 100644
--- a/compiler/rustc_mir/src/dataflow/framework/graphviz.rs
+++ b/compiler/rustc_mir/src/dataflow/framework/graphviz.rs
@@ -578,7 +578,7 @@ where
         return String::new();
     }
 
-    let re = Regex::new("\u{001f}([+-])").unwrap();
+    let re = Regex::new("\t?\u{001f}([+-])").unwrap();
 
     let raw_diff = format!("{:#?}", DebugDiffWithAdapter { new, old, ctxt });