diff --git a/bolt/lib/Passes/BinaryPasses.cpp b/bolt/lib/Passes/BinaryPasses.cpp
--- a/bolt/lib/Passes/BinaryPasses.cpp
+++ b/bolt/lib/Passes/BinaryPasses.cpp
@@ -1015,6 +1015,7 @@
         continue;
 
       if (opts::Verbosity > 2) {
+        BC.scopeLock();
         outs() << "BOLT-INFO: shortening:\nBOLT-INFO:    ";
         BC.printInstruction(outs(), OriginalInst, 0, &Function);
         outs() << "BOLT-INFO: to:";