diff --git a/gold/merge.cc b/gold/merge.cc
index 15d3b7cd1b..0c4256ba7a 100644
--- a/gold/merge.cc
+++ b/gold/merge.cc
@@ -35,7 +35,7 @@ namespace gold
 // Sort the entries in a merge mapping.  The key is an input object, a
 // section index in that object, and an offset in that section.
 
-bool
+inline bool
 Merge_map::Merge_key_less::operator()(const Merge_key& mk1,
 				      const Merge_key& mk2) const
 {
diff --git a/gold/merge.h b/gold/merge.h
index 630b5936ec..1f750c5477 100644
--- a/gold/merge.h
+++ b/gold/merge.h
@@ -70,7 +70,7 @@ class Merge_map
 
   struct Merge_key_less
   {
-    bool
+    inline bool
     operator()(const Merge_key&, const Merge_key&) const;
   };