diff --git a/ArcFormats/KiriKiri/ArcXP3.cs b/ArcFormats/KiriKiri/ArcXP3.cs
index cd420145..23d82c6d 100644
--- a/ArcFormats/KiriKiri/ArcXP3.cs
+++ b/ArcFormats/KiriKiri/ArcXP3.cs
@@ -146,7 +146,7 @@ namespace GameRes.Formats.KiriKiri
                     header_stream = ZLibCompressor.DeCompress (input);
             }
 
-            var crypt_algorithm = new Lazy<ICrypt> (QueryCryptAlgorithm);
+            var crypt_algorithm = new Lazy<ICrypt> (QueryCryptAlgorithm, false);
 
             var filename_map = new Dictionary<uint, string>();
             var dir = new List<Entry>();
diff --git a/ArcFormats/Tactics/ArcTactics.cs b/ArcFormats/Tactics/ArcTactics.cs
index 3b93c991..85d2e646 100644
--- a/ArcFormats/Tactics/ArcTactics.cs
+++ b/ArcFormats/Tactics/ArcTactics.cs
@@ -127,7 +127,7 @@ namespace GameRes.Formats.Tactics
                 m_packed_size = m_file.View.ReadUInt32 (0x10);
                 m_unpacked_size = m_file.View.ReadUInt32 (0x14);
                 m_count = m_file.View.ReadInt32 (0x18);
-                m_dir = new Lazy<List<Entry>> (() => new List<Entry> (m_count));
+                m_dir = new Lazy<List<Entry>> (() => new List<Entry> (m_count), false);
             }
 
             public List<Entry> ReadIndex ()
diff --git a/GameRes/ArcFile.cs b/GameRes/ArcFile.cs
index 6e9bbf65..51a6586d 100644
--- a/GameRes/ArcFile.cs
+++ b/GameRes/ArcFile.cs
@@ -72,7 +72,7 @@ namespace GameRes
             if (entry.Size < 4)
                 return null;
             var filename = entry.Name;
-            var ext = new Lazy<string> (() => Path.GetExtension (filename).TrimStart ('.').ToLowerInvariant());
+            var ext = new Lazy<string> (() => Path.GetExtension (filename).TrimStart ('.').ToLowerInvariant(), false);
             var file = VFS.OpenView (entry);
             try
             {
diff --git a/GameRes/Image.cs b/GameRes/Image.cs
index 8c7e3d77..44799097 100644
--- a/GameRes/Image.cs
+++ b/GameRes/Image.cs
@@ -157,7 +157,7 @@ namespace GameRes
             uint signature = FormatCatalog.ReadSignature (file);
             Lazy<string> ext = null;
             if (!string.IsNullOrEmpty (filename))
-                ext = new Lazy<string> (() => Path.GetExtension (filename).TrimStart ('.').ToLowerInvariant());
+                ext = new Lazy<string> (() => Path.GetExtension (filename).TrimStart ('.').ToLowerInvariant(), false);
             for (;;)
             {
                 var range = FormatCatalog.Instance.LookupSignature<ImageFormat> (signature);