Index: src/OFConcreteNumber.h
==================================================================
--- src/OFConcreteNumber.h
+++ src/OFConcreteNumber.h
@@ -22,10 +22,10 @@
 	union {
 		double float_;
 		long long signed_;
 		unsigned long long unsigned_;
 	} _value;
-	const char *_typeEncoding;
+	char _typeEncoding;
 }
 @end
 
 OF_ASSUME_NONNULL_END

Index: src/OFConcreteNumber.m
==================================================================
--- src/OFConcreteNumber.m
+++ src/OFConcreteNumber.m
@@ -96,101 +96,101 @@
 - (instancetype)initWithBool: (bool)value
 {
 	self = [super initWithBytes: &value objCType: @encode(bool)];
 
 	_value.unsigned_ = value;
-	_typeEncoding = @encode(bool);
+	_typeEncoding = *@encode(bool);
 
 	return self;
 }
 
 - (instancetype)initWithChar: (signed char)value
 {
 	self = [super initWithBytes: &value objCType: @encode(signed char)];
 
 	_value.signed_ = value;
-	_typeEncoding = @encode(signed char);
+	_typeEncoding = *@encode(signed char);
 
 	return self;
 }
 
 - (instancetype)initWithShort: (short)value
 {
 	self = [super initWithBytes: &value objCType: @encode(short)];
 
 	_value.signed_ = value;
-	_typeEncoding = @encode(short);
+	_typeEncoding = *@encode(short);
 
 	return self;
 }
 
 - (instancetype)initWithInt: (int)value
 {
 	self = [super initWithBytes: &value objCType: @encode(int)];
 
 	_value.signed_ = value;
-	_typeEncoding = @encode(int);
+	_typeEncoding = *@encode(int);
 
 	return self;
 }
 
 - (instancetype)initWithLong: (long)value
 {
 	self = [super initWithBytes: &value objCType: @encode(long)];
 
 	_value.signed_ = value;
-	_typeEncoding = @encode(long);
+	_typeEncoding = *@encode(long);
 
 	return self;
 }
 
 - (instancetype)initWithLongLong: (long long)value
 {
 	self = [super initWithBytes: &value objCType: @encode(long long)];
 
 	_value.signed_ = value;
-	_typeEncoding = @encode(long long);
+	_typeEncoding = *@encode(long long);
 
 	return self;
 }
 
 - (instancetype)initWithUnsignedChar: (unsigned char)value
 {
 	self = [super initWithBytes: &value objCType: @encode(unsigned char)];
 
 	_value.unsigned_ = value;
-	_typeEncoding = @encode(unsigned long);
+	_typeEncoding = *@encode(unsigned long);
 
 	return self;
 }
 
 - (instancetype)initWithUnsignedShort: (unsigned short)value
 {
 	self = [super initWithBytes: &value objCType: @encode(unsigned short)];
 
 	_value.unsigned_ = value;
-	_typeEncoding = @encode(unsigned short);
+	_typeEncoding = *@encode(unsigned short);
 
 	return self;
 }
 
 - (instancetype)initWithUnsignedInt: (unsigned int)value
 {
 	self = [super initWithBytes: &value objCType: @encode(unsigned int)];
 
 	_value.unsigned_ = value;
-	_typeEncoding = @encode(unsigned int);
+	_typeEncoding = *@encode(unsigned int);
 
 	return self;
 }
 
 - (instancetype)initWithUnsignedLong: (unsigned long)value
 {
 	self = [super initWithBytes: &value objCType: @encode(unsigned long)];
 
 	_value.unsigned_ = value;
-	_typeEncoding = @encode(unsigned long);
+	_typeEncoding = *@encode(unsigned long);
 
 	return self;
 }
 
 - (instancetype)initWithUnsignedLongLong: (unsigned long long)value
@@ -197,38 +197,38 @@
 {
 	self = [super initWithBytes: &value
 			   objCType: @encode(unsigned long long)];
 
 	_value.unsigned_ = value;
-	_typeEncoding = @encode(unsigned long long);
+	_typeEncoding = *@encode(unsigned long long);
 
 	return self;
 }
 
 - (instancetype)initWithFloat: (float)value
 {
 	self = [super initWithBytes: &value objCType: @encode(float)];
 
 	_value.float_ = value;
-	_typeEncoding = @encode(float);
+	_typeEncoding = *@encode(float);
 
 	return self;
 }
 
 - (instancetype)initWithDouble: (double)value
 {
 	self = [super initWithBytes: &value objCType: @encode(double)];
 
 	_value.float_ = value;
-	_typeEncoding = @encode(double);
+	_typeEncoding = *@encode(double);
 
 	return self;
 }
 
 - (const char *)objCType
 {
-	return _typeEncoding;
+	return &_typeEncoding;
 }
 
 - (long long)longLongValue
 {
 	if (isFloat(self))

Index: src/OFConcreteValue.h
==================================================================
--- src/OFConcreteValue.h
+++ src/OFConcreteValue.h
@@ -19,10 +19,10 @@
 
 @interface OFConcreteValue: OFValue
 {
 	size_t _size;
 	void *_bytes;
-	const char *_objCType;
+	char *_objCType;
 }
 @end
 
 OF_ASSUME_NONNULL_END

Index: src/OFConcreteValue.m
==================================================================
--- src/OFConcreteValue.m
+++ src/OFConcreteValue.m
@@ -13,10 +13,11 @@
  * file.
  */
 
 #import "OFConcreteValue.h"
 #import "OFMethodSignature.h"
+#import "OFString.h"
 
 #import "OFOutOfRangeException.h"
 
 @implementation OFConcreteValue
 @synthesize objCType = _objCType;
@@ -26,13 +27,12 @@
 {
 	self = [super initWithBytes: bytes objCType: objCType];
 
 	@try {
 		_size = OFSizeOfTypeEncoding(objCType);
-		_objCType = objCType;
+		_objCType = OFStrDup(objCType);
 		_bytes = OFAllocMemory(1, _size);
-
 		memcpy(_bytes, bytes, _size);
 	} @catch (id e) {
 		[self release];
 		@throw e;
 	}
@@ -41,10 +41,11 @@
 }
 
 - (void)dealloc
 {
 	OFFreeMemory(_bytes);
+	OFFreeMemory(_objCType);
 
 	[super dealloc];
 }
 
 - (void)getValue: (void *)value size: (size_t)size