Index: src/OFMutableZIPArchiveEntry.h
==================================================================
--- src/OFMutableZIPArchiveEntry.h
+++ src/OFMutableZIPArchiveEntry.h
@@ -90,16 +90,16 @@
     OFZIPArchiveEntryCompressionMethod compressionMethod;
 
 /**
  * @brief The compressed size of the entry's file.
  */
-@property (readwrite, nonatomic) uint64_t compressedSize;
+@property (readwrite, nonatomic) unsigned long long compressedSize;
 
 /**
  * @brief The uncompressed size of the entry's file.
  */
-@property (readwrite, nonatomic) uint64_t uncompressedSize;
+@property (readwrite, nonatomic) unsigned long long uncompressedSize;
 
 /**
  * @brief The CRC32 checksum of the entry's file.
  */
 @property (readwrite, nonatomic) uint32_t CRC32;

Index: src/OFMutableZIPArchiveEntry.m
==================================================================
--- src/OFMutableZIPArchiveEntry.m
+++ src/OFMutableZIPArchiveEntry.m
@@ -140,16 +140,16 @@
     (OFZIPArchiveEntryCompressionMethod)compressionMethod
 {
 	_compressionMethod = compressionMethod;
 }
 
-- (void)setCompressedSize: (uint64_t)compressedSize
+- (void)setCompressedSize: (unsigned long long)compressedSize
 {
 	_compressedSize = compressedSize;
 }
 
-- (void)setUncompressedSize: (uint64_t)uncompressedSize
+- (void)setUncompressedSize: (unsigned long long)uncompressedSize
 {
 	_uncompressedSize = uncompressedSize;
 }
 
 - (void)setCRC32: (uint32_t)CRC32

Index: src/OFZIPArchive.m
==================================================================
--- src/OFZIPArchive.m
+++ src/OFZIPArchive.m
@@ -81,11 +81,11 @@
 OF_DIRECT_MEMBERS
 @interface OFZIPArchiveFileReadStream: OFStream
 {
 	OFStream *_stream, *_decompressedStream;
 	OFZIPArchiveEntry *_entry;
-	uint64_t _toRead;
+	unsigned long long _toRead;
 	uint32_t _CRC32;
 	bool _atEndOfStream;
 }
 
 - (instancetype)of_initWithStream: (OFStream *)stream
@@ -96,11 +96,11 @@
 @interface OFZIPArchiveFileWriteStream: OFStream
 {
 	OFStream *_stream;
 	uint32_t _CRC32;
 @public
-	int64_t _bytesWritten;
+	unsigned long long _bytesWritten;
 	OFMutableZIPArchiveEntry *_entry;
 }
 
 - (instancetype)initWithStream: (OFStream *)stream
 			 entry: (OFMutableZIPArchiveEntry *)entry;
@@ -408,11 +408,11 @@
 	    [_lastReturnedStream isKindOfClass:
 	    [OFZIPArchiveFileWriteStream class]]) {
 		OFZIPArchiveFileWriteStream *stream =
 		    (OFZIPArchiveFileWriteStream *)_lastReturnedStream;
 
-		if (INT64_MAX - _offset < stream->_bytesWritten)
+		if (ULLONG_MAX - _offset < stream->_bytesWritten)
 			@throw [OFOutOfRangeException exception];
 
 		_offset += stream->_bytesWritten;
 
 		if (stream->_entry != nil) {
@@ -801,11 +801,11 @@
 #if SIZE_MAX >= UINT64_MAX
 	if (length > UINT64_MAX)
 		@throw [OFOutOfRangeException exception];
 #endif
 
-	if ((uint64_t)length > _toRead)
+	if (length > _toRead)
 		length = (size_t)_toRead;
 
 	ret = [_decompressedStream readIntoBuffer: buffer length: length];
 
 	_toRead -= ret;
@@ -884,28 +884,28 @@
 #if SIZE_MAX >= INT64_MAX
 	if (length > INT64_MAX)
 		@throw [OFOutOfRangeException exception];
 #endif
 
-	if (INT64_MAX - _bytesWritten < (int64_t)length)
+	if (ULLONG_MAX - _bytesWritten < length)
 		@throw [OFOutOfRangeException exception];
 
 	@try {
 		[_stream writeBuffer: buffer length: length];
 	} @catch (OFWriteFailedException *e) {
 		OFEnsure(e.bytesWritten <= length);
 
-		_bytesWritten += (int64_t)e.bytesWritten;
+		_bytesWritten += e.bytesWritten;
 		_CRC32 = OFCRC32(_CRC32, buffer, e.bytesWritten);
 
 		if (e.errNo == EWOULDBLOCK || e.errNo == EAGAIN)
 			return e.bytesWritten;
 
 		@throw e;
 	}
 
-	_bytesWritten += (int64_t)length;
+	_bytesWritten += length;
 	_CRC32 = OFCRC32(_CRC32, buffer, length);
 
 	return length;
 }
 
@@ -912,14 +912,17 @@
 - (void)close
 {
 	if (_stream == nil)
 		@throw [OFNotOpenException exceptionWithObject: self];
 
+	if (_bytesWritten > UINT64_MAX)
+		@throw [OFOutOfRangeException exception];
+
 	[_stream writeLittleEndianInt32: 0x08074B50];
 	[_stream writeLittleEndianInt32: _CRC32];
-	[_stream writeLittleEndianInt64: _bytesWritten];
-	[_stream writeLittleEndianInt64: _bytesWritten];
+	[_stream writeLittleEndianInt64: (uint64_t)_bytesWritten];
+	[_stream writeLittleEndianInt64: (uint64_t)_bytesWritten];
 
 	[_stream release];
 	_stream = nil;
 
 	_entry.CRC32 = ~_CRC32;

Index: src/OFZIPArchiveEntry.h
==================================================================
--- src/OFZIPArchiveEntry.h
+++ src/OFZIPArchiveEntry.h
@@ -106,11 +106,11 @@
 	OFZIPArchiveEntryAttributeCompatibility _minVersionNeeded;
 	uint16_t _generalPurposeBitFlag;
 	OFZIPArchiveEntryCompressionMethod _compressionMethod;
 	uint16_t _lastModifiedFileTime, _lastModifiedFileDate;
 	uint32_t _CRC32;
-	uint64_t _compressedSize, _uncompressedSize;
+	unsigned long long _compressedSize, _uncompressedSize;
 	OFString *_fileName;
 	OFData *_Nullable _extraField;
 	OFString *_Nullable _fileComment;
 	uint32_t _startDiskNumber;
 	uint16_t _internalAttributes;
@@ -180,16 +180,16 @@
     OFZIPArchiveEntryCompressionMethod compressionMethod;
 
 /**
  * @brief The compressed size of the entry's file.
  */
-@property (readonly, nonatomic) uint64_t compressedSize;
+@property (readonly, nonatomic) unsigned long long compressedSize;
 
 /**
  * @brief The uncompressed size of the entry's file.
  */
-@property (readonly, nonatomic) uint64_t uncompressedSize;
+@property (readonly, nonatomic) unsigned long long uncompressedSize;
 
 /**
  * @brief The CRC32 checksum of the entry's file.
  */
 @property (readonly, nonatomic) uint32_t CRC32;

Index: src/OFZIPArchiveEntry.m
==================================================================
--- src/OFZIPArchiveEntry.m
+++ src/OFZIPArchiveEntry.m
@@ -364,16 +364,16 @@
 - (OFZIPArchiveEntryCompressionMethod)compressionMethod
 {
 	return _compressionMethod;
 }
 
-- (uint64_t)compressedSize
+- (unsigned long long)compressedSize
 {
 	return _compressedSize;
 }
 
-- (uint64_t)uncompressedSize
+- (unsigned long long)uncompressedSize
 {
 	return _uncompressedSize;
 }
 
 - (uint32_t)CRC32

Index: utils/ofarc/ZIPArchive.m
==================================================================
--- utils/ofarc/ZIPArchive.m
+++ utils/ofarc/ZIPArchive.m
@@ -246,11 +246,11 @@
 		void *pool = objc_autoreleasePoolPush();
 		OFString *fileName = entry.fileName;
 		OFString *outFileName, *directory;
 		OFStream *stream;
 		OFFile *output;
-		uint64_t written = 0, size = entry.uncompressedSize;
+		unsigned long long written = 0, size = entry.uncompressedSize;
 		int8_t percent = -1, newPercent;
 
 		if (!all && ![files containsObject: fileName])
 			continue;
 
@@ -437,15 +437,15 @@
 			    @"file", fileName)];
 
 		entry = [OFMutableZIPArchiveEntry entryWithFileName: fileName];
 
 		size = (isDirectory ? 0 : attributes.fileSize);
-		if (size > INT64_MAX)
+		if (size < 0 || size > ULLONG_MAX)
 			@throw [OFOutOfRangeException exception];
 
-		entry.compressedSize = (int64_t)size;
-		entry.uncompressedSize = (int64_t)size;
+		entry.compressedSize = size;
+		entry.uncompressedSize = size;
 
 		entry.compressionMethod =
 		    OFZIPArchiveEntryCompressionMethodNone;
 		entry.modificationDate = attributes.fileModificationDate;