Index: src/OFDate.m
==================================================================
--- src/OFDate.m
+++ src/OFDate.m
@@ -37,10 +37,11 @@
 #import "OFXMLElement.h"
 
 #import "OFInitializationFailedException.h"
 #import "OFInvalidArgumentException.h"
 #import "OFInvalidFormatException.h"
+#import "OFOutOfMemoryException.h"
 #import "OFOutOfRangeException.h"
 
 #import "of_strptime.h"
 
 #ifdef OF_AMIGAOS_M68K
@@ -55,16 +56,28 @@
 @interface OFDateSingleton: OFDate
 @end
 
 @interface OFDatePlaceholder: OFDateSingleton
 @end
+
+#if defined(OF_OBJFW_RUNTIME) && UINTPTR_MAX == UINT64_MAX
+@interface OFTaggedPointerDate: OFDateSingleton
+@end
+#endif
 
 static struct {
 	Class isa;
 } placeholder;
 
-static OFDateSingleton *distantFuture, *distantPast;
+static OFDateSingleton *zeroDate, *distantFuture, *distantPast;
+static int dateTag;
+
+static void
+initZeroDate(void)
+{
+	zeroDate = [[OFDateSingleton alloc] initWithTimeIntervalSince1970: 0];
+}
 
 static void
 initDistantFuture(void)
 {
 	distantFuture = [[OFDateSingleton alloc]
@@ -268,16 +281,54 @@
 # pragma clang diagnostic push
 # pragma clang diagnostic ignored "-Wobjc-designated-initializers"
 #endif
 - (instancetype)initWithTimeIntervalSince1970: (of_time_interval_t)seconds
 {
+#if defined(OF_OBJFW_RUNTIME) && UINTPTR_MAX == UINT64_MAX
+	uint64_t value;
+#endif
+
+	if (seconds == 0) {
+		static of_once_t once = OF_ONCE_INIT;
+		of_once(&once, initZeroDate);
+		return (id)zeroDate;
+	}
+
+#if defined(OF_OBJFW_RUNTIME) && UINTPTR_MAX == UINT64_MAX
+	value = OF_BSWAP64_IF_LE(OF_DOUBLE_TO_INT_RAW(OF_BSWAP_DOUBLE_IF_LE(
+	    seconds)));
+
+	/* Almost all dates fall into this range. */
+	if (value & (UINT64_C(4) << 60)) {
+		id ret = objc_createTaggedPointer(dateTag,
+		    value & ~(UINT64_C(4) << 60));
+
+		if (ret != nil)
+			return ret;
+	}
+#endif
+
 	return (id)[[OFDate of_alloc] initWithTimeIntervalSince1970: seconds];
 }
 #ifdef __clang__
 # pragma clang diagnostic pop
 #endif
 @end
+
+#if defined(OF_OBJFW_RUNTIME) && UINTPTR_MAX == UINT64_MAX
+@implementation OFTaggedPointerDate
+- (of_time_interval_t)timeIntervalSince1970
+{
+	uint64_t value = (uint64_t)object_getTaggedPointerValue(self);
+
+	value |= UINT64_C(4) << 60;
+
+	return OF_BSWAP_DOUBLE_IF_LE(OF_INT_TO_DOUBLE_RAW(OF_BSWAP64_IF_LE(
+	    value)));
+}
+@end
+#endif
 
 @implementation OFDate
 + (void)initialize
 {
 #ifdef OF_WINDOWS
@@ -297,10 +348,14 @@
 #ifdef OF_WINDOWS
 	if ((module = LoadLibrary("msvcrt.dll")) != NULL)
 		func__mktime64 = (__time64_t (*)(struct tm *))
 		    GetProcAddress(module, "_mktime64");
 #endif
+
+#if defined(OF_OBJFW_RUNTIME) && UINTPTR_MAX == UINT64_MAX
+	dateTag = objc_registerTaggedPointerClass([OFTaggedPointerDate class]);
+#endif
 }
 
 + (instancetype)of_alloc
 {
 	return [super alloc];
@@ -509,11 +564,11 @@
 - (OFXMLElement *)XMLElementBySerializing
 {
 	void *pool = objc_autoreleasePoolPush();
 	OFXMLElement *element;
 
-	element = [OFXMLElement elementWithName: self.className
+	element = [OFXMLElement elementWithName: @"OFDate"
 				      namespace: OF_SERIALIZATION_NS];
 
 	element.stringValue = [OFString stringWithFormat: @"%016" PRIx64,
 	    OF_BSWAP64_IF_LE(OF_DOUBLE_TO_INT_RAW(OF_BSWAP_DOUBLE_IF_LE(
 	    self.timeIntervalSince1970)))];
@@ -701,11 +756,13 @@
 	}
 # endif
 #endif
 
 	pageSize = [OFSystemInfo pageSize];
-	buffer = [self allocMemoryWithSize: pageSize];
+	if ((buffer = malloc(pageSize)) == NULL)
+		@throw [OFOutOfMemoryException
+		    exceptionWithRequestedSize: pageSize];
 
 	@try {
 #ifndef OF_WINDOWS
 		if (strftime(buffer, pageSize, format.UTF8String, &tm) == 0)
 			@throw [OFOutOfRangeException exception];
@@ -717,11 +774,11 @@
 			@throw [OFOutOfRangeException exception];
 
 		ret = [OFString stringWithUTF16String: buffer];
 #endif
 	} @finally {
-		[self freeMemory: buffer];
+		free(buffer);
 	}
 
 	return ret;
 }
 
@@ -762,11 +819,13 @@
 	}
 # endif
 #endif
 
 	pageSize = [OFSystemInfo pageSize];
-	buffer = [self allocMemoryWithSize: pageSize];
+	if ((buffer = malloc(pageSize)) == NULL)
+		@throw [OFOutOfMemoryException
+		    exceptionWithRequestedSize: pageSize];
 
 	@try {
 #ifndef OF_WINDOWS
 		if (strftime(buffer, pageSize, format.UTF8String, &tm) == 0)
 			@throw [OFOutOfRangeException exception];
@@ -778,11 +837,11 @@
 			@throw [OFOutOfRangeException exception];
 
 		ret = [OFString stringWithUTF16String: buffer];
 #endif
 	} @finally {
-		[self freeMemory: buffer];
+		free(buffer);
 	}
 
 	return ret;
 }