diff --git a/dbms/src/Compression/CompressionCodecLZ4.cpp b/dbms/src/Compression/CompressionCodecLZ4.cpp
index 5181ee3df94..08553e0920c 100644
--- a/dbms/src/Compression/CompressionCodecLZ4.cpp
+++ b/dbms/src/Compression/CompressionCodecLZ4.cpp
@@ -20,7 +20,6 @@ namespace DB
 namespace ErrorCodes
 {
 extern const int CANNOT_COMPRESS;
-extern const int CANNOT_DECOMPRESS;
 extern const int ILLEGAL_SYNTAX_FOR_CODEC_TYPE;
 extern const int ILLEGAL_CODEC_PARAMETER;
 }
@@ -48,8 +47,6 @@ UInt32 CompressionCodecLZ4::doCompressData(const char * source, UInt32 source_si
 
 void CompressionCodecLZ4::doDecompressData(const char * source, UInt32 source_size, char * dest, UInt32 uncompressed_size) const
 {
-    // if (LZ4_decompress_safe(source, dest, source_size, uncompressed_size) < 0)
-        // throw Exception("Cannot LZ4_decompress_fast", ErrorCodes::CANNOT_DECOMPRESS);
     LZ4::decompress(source, dest, source_size, uncompressed_size, lz4_stat);
 }