DELPHI 32位与64位数据类型大小

Delphi 32-bit and 64-bit Windows built-in type sizes

Integral types

On Win64, NativeInt is twice the size of the Win32 NativeInt, and NativeUInt is twice the size of the Win32 NativeUInt.

Signed Integer	Unsigned Integer	Delphi/32	Delphi/64	Comments
ShortInt	Byte	1 byte
SmallInt	Word	2 bytes
LongInt	LongWord	4 bytes
Integer	Cardinal	4 bytes
Int64	UInt64	8 bytes
NativeInt	NativeUInt	4 bytes	8 bytes

Pointer types

On 64-bit Windows, all pointer types are 8 bytes, twice the size on 32-bit Windows.

Pointer types	Delphi/32	Delphi/64
Pointer	4 bytes	8 bytes
string
class instance
class reference
interface
AnsiString
WideString
UnicodeString
procedure pointer
dynamic array
PAnsiChar
PWideChar
PChar

Procedure of object

On 64-bit Windows, the alignment for a procedure of object is 16 bytes, twice the size on 32-bit Windows.

procedure of object	8 bytes	16 bytes
	8 byte align	8 byte align	Known as closure type

Floating-point types (including the Extended data type)

The Extended type has 2 bytes' worth less precision on 64-bit Windows than on 32-bit Windows (8 bytes vs 10 bytes)..

For more information, see The Extended Data Type Is 2 Bytes Smaller on 64-bit Windows Systems.

Floating point types	Delphi/32	Delphi/64	Comments
Single	4 bytes
Double	8 bytes
Real	8 bytes
Extended	10 bytes	8 bytes	TExtended80Rec has 10 bytes on Win64
Real48	6 bytes
Comp	8 bytes
Currency	8 bytes

Other types

On Win64, file size has increased.

Other types	Delphi/32	Delphi/64	Comments
Boolean	1 byte
ByteBool	1 byte
WordBool	2 bytes
LongBool	4 bytes
AnsiChar	1 byte
WideChar	2 bytes
Char	2 bytes
ShortString	256 bytes
string[N]	N+1 bytes
Variant / OleVariant	16 bytes		24 bytes
file	592 bytes	616 bytes
Text / TextFile	730 bytes	754 bytes	720 bytes in XE release

Constants

Constants	Delphi/32	Delphi/64
MaxInt	$7fffffff
MaxLongInt	$7fffffff