@@ -516,11 +516,11 @@
 	entry.versionMadeBy = (entry.versionMadeBy & 0xFF00) | 45;
 	entry.minVersionNeeded = (entry.minVersionNeeded & 0xFF00) | 45;
 	entry.compressedSize = 0;
 	entry.uncompressedSize = 0;
 	entry.CRC32 = 0;
-	entry.generalPurposeBitFlag |= (1 << 3) | (1 << 11);
+	entry.generalPurposeBitFlag |= (1u << 3) | (1u << 11);
 	entry.of_localFileHeaderOffset = _offset;
 
 	[_stream writeLittleEndianInt32: 0x04034B50];
 	[_stream writeLittleEndianInt16: entry.minVersionNeeded];
 	[_stream writeLittleEndianInt16: entry.generalPurposeBitFlag];
@@ -654,11 +654,11 @@
 		_CRC32 = [stream readLittleEndianInt32];
 		_compressedSize = [stream readLittleEndianInt32];
 		_uncompressedSize = [stream readLittleEndianInt32];
 		fileNameLength = [stream readLittleEndianInt16];
 		extraFieldLength = [stream readLittleEndianInt16];
-		encoding = (_generalPurposeBitFlag & (1 << 11)
+		encoding = (_generalPurposeBitFlag & (1u << 11)
 		    ? OF_STRING_ENCODING_UTF_8
 		    : OF_STRING_ENCODING_CODEPAGE_437);
 
 		_fileName = [[stream readStringWithLength: fileNameLength
 						 encoding: encoding] copy];
@@ -715,11 +715,11 @@
 	if (_compressionMethod != entry.compressionMethod ||
 	    _lastModifiedFileTime != entry.of_lastModifiedFileTime ||
 	    _lastModifiedFileDate != entry.of_lastModifiedFileDate)
 		return false;
 
-	if (!(_generalPurposeBitFlag & (1 << 3)))
+	if (!(_generalPurposeBitFlag & (1u << 3)))
 		if (_CRC32 != entry.CRC32 ||
 		    _compressedSize != entry.compressedSize ||
 		    _uncompressedSize != entry.uncompressedSize)
 			return false;