diff --git a/llvm/lib/ExecutionEngine/JITLink/JITLink_MachO_x86_64.cpp b/llvm/lib/ExecutionEngine/JITLink/JITLink_MachO_x86_64.cpp
index 6ee633baca4c..857885bee105 100644
--- a/llvm/lib/ExecutionEngine/JITLink/JITLink_MachO_x86_64.cpp
+++ b/llvm/lib/ExecutionEngine/JITLink/JITLink_MachO_x86_64.cpp
@@ -91,7 +91,7 @@ private:
         "Unsupported x86-64 relocation: kind=" + formatv("{0:x1}", RI.r_type) +
         ", pc_rel=" + (RI.r_pcrel ? "true" : "false") +
         ", extern= " + (RI.r_extern ? "true" : "false") +
-        ", length=" + formatv("{0:u}", RI.r_length));
+        ", length=" + formatv("{0:d}", RI.r_length));
   }
 
   Expected<Atom &> findAtomBySymbolIndex(const MachO::relocation_info &RI) {