diff --git a/lz4diff/lz4diff_compress.cc b/lz4diff/lz4diff_compress.cc
index 67b02de..930954b 100644
--- a/lz4diff/lz4diff_compress.cc
+++ b/lz4diff/lz4diff_compress.cc
@@ -131,7 +131,7 @@
     compressed_size += block.compressed_length;
   }
   if (blob.size() < compressed_size) {
-    LOG(INFO) << "File is chunked. Skip lz4 decompress.Expected size : "
+    LOG(INFO) << "File is chunked. Skip lz4 decompress. Expected size: "
               << compressed_size << ", actual size: " << blob.size();
     return {};
   }
diff --git a/lz4diff/lz4patch.h b/lz4diff/lz4patch.h
index 8f66180..ce49430 100644
--- a/lz4diff/lz4patch.h
+++ b/lz4diff/lz4patch.h
@@ -26,6 +26,8 @@
               Blob* output);
 bool Lz4Patch(const Blob& src_data, const Blob& patch_data, Blob* output);
 
+std::ostream& operator<<(std::ostream& out, const CompressionAlgorithm& info);
+
 std::ostream& operator<<(std::ostream& out, const Lz4diffHeader&);
 
 template <typename T>