diff --git a/compiler/optimizing/nodes.h b/compiler/optimizing/nodes.h
index d6dfeae..7298e25 100644
--- a/compiler/optimizing/nodes.h
+++ b/compiler/optimizing/nodes.h
@@ -192,7 +192,8 @@
   HLoopInformation(HBasicBlock* header, HGraph* graph)
       : header_(header),
         back_edges_(graph->GetArena(), kDefaultNumberOfBackEdges),
-        blocks_(graph->GetArena(), graph->GetBlocks().Size(), false) {}
+        // Make bit vector growable, as the number of blocks may change.
+        blocks_(graph->GetArena(), graph->GetBlocks().Size(), true) {}
 
   HBasicBlock* GetHeader() const {
     return header_;