Which integer types have their size dependent on platform? E.g. in Delphi, LongInt can 32 or 64 bits depending on the platform. The documentation says "every platform has a ”native” integer size, depending on whether the platform is 8-bit, 16-bit, 32-bit or 64-bit. e.g. On AVR this is 8-bit. ", but it is not clear about which integer types are "natives".

Regards

Which integer types have their size dependent on platform? E.g. in Delphi, LongInt can 32 or 64 bits depending on the platform.

Why do you think that Delphi's longint has 64bits anywhere? Delphi's NativeInt is 32 or 64bit depending on platform.

The documentation says "every platform has a ”native” integer size, depending on whether the platform is 8-bit, 16-bit, 32-bit or 64-bit. e.g. On AVR this is 8-bit. ", but it is not clear about which integer types are "natives".

Most of FPC's integer types defined via IFDFEs. See fpc/rtl/inc/systemh.inc
You can use Lazarus' Find Declaration on any type and see the definition.
For example:

{$ifdef CPU64}
  SizeInt = Int64;
  SizeUInt = QWord;
  PtrInt = Int64;
  PtrUInt = QWord;
  ValSInt = int64;
  ValUInt = qword;
  CodePointer = Pointer;
  CodePtrInt = PtrInt;
  CodePtrUInt = PtrUInt;
{$endif CPU64}
{$ifdef CPU32}
  SizeInt = Longint;
  SizeUInt = DWord;
  PtrInt = Longint;
  PtrUInt = DWord;
  ValSInt = Longint;
  ValUInt = Cardinal;
  CodePointer = Pointer;
  CodePtrInt = PtrInt;
  CodePtrUInt = PtrUInt;
{$endif CPU32}
  { NativeInt and NativeUInt are Delphi compatibility types. Even though Delphi
    has IntPtr and UIntPtr, the Delphi documentation for NativeInt states that
    'The size of NativeInt is equivalent to the size of the pointer on the
    current platform'. Because of the misleading names, these types shouldn't be
    used in the FPC RTL. Note that on i8086 their size changes between 16-bit
    and 32-bit according to the memory model, so they're not really a 'native
    int' type there at all. }
  NativeInt  = PtrInt;
  NativeUInt = PtrUInt;

Mattias

In our previous episode, African Wild Dog said:

Which integer types have their size dependent on platform? E.g. in Delphi, LongInt can 32 or 64 bits depending on the platform.

In Delphi they retroactively equated longint to C long, being 32-bit on 64-bits windows and 64-bit on Linux. The Delphi Linux compiler is btw a different compiler than windows.

On FPC it is always 32-bit. Ptrint and ptruint scale with pointer size, and integer depends on compilation mode, 16 or 32-bit.

For the C compiler that FPC corresponds with (usually gcc), there are types that correspond with C types in unit ctypes.

Maybe some of the new ultra small targets like AVR make exceptions, but those are the general rules.

On AVR this is 8-bit. ", but it is not clear about which integer types are "natives".

The typical pascal solution is to use subranges and hope the compiler will optimize it.

2017-04-07 11:15 GMT-03:00 Marco van de Voort :

So, is the size of "Integer" type dependent on the compilation mode? (Delphi is always 32 bits)

2017-04-06 18:50 GMT-03:00 Mattias Gaertner :

Why do you think that Delphi's longint has 64bits anywhere? Delphi's NativeInt is 32 or 64bit depending on platform.

http://docwiki.embarcadero.com/RADStudio/Tokyo/en/Internal_Data_Formats_(Delphi)#Platform-Independent_Signed_Integer_Types .
As Marco have pointed out, in Windows the Delphi's LongInt type is always 32-bits. On other platforms is platform dependent.

Still not clear for me. Are NativeInt and NativeUInt provided for Delphi compatibility, right? So, if i need an integer type which depends on platform/fpc compilation mode, which one should i use?

In our previous episode, African Wild Dog said:

> On FPC it is always 32-bit. Ptrint and ptruint scale with pointer size, and > integer depends on compilation mode, 16 or 32-bit. > So, is the size of "Integer" type dependent on the compilation mode?

Yes.

(Delphi is always 32 bits)

In objfpc and delphi modes it is 32-bit, in more TP oriented modes it is 16-bit as it was in TP.

Yes. It is 16 bit in fpc/tp mode, 32 bit in Delphi/ObjFPC and MacPas.

Michael.

In short: It is platform dependent in Delphi.

Still not clear for me. Are NativeInt and NativeUInt provided for Delphi compatibility, right? So, if i need an integer type which depends on platform/fpc compilation mode, which one should i use?

NativeInt and NativeUInt are indeed provided for Delphi compatibility.

Which integer type to chose : That depends.
What do you want to achieve exactly ?

Michael.

In our previous episode, African Wild Dog said:

Note that this is a very recent development. It started with the iOS 64-bit arm compiler a while back, and now since weeks their new Linux offering.

Both however are a different compiler than the regular.

Still not clear for me. Are NativeInt and NativeUInt provided for Delphi compatibility, right? So, if i need an integer type which depends on platform/fpc compilation mode, which one should i use?

For what purpose? There are only ones that scale with pointer size, and then any of the native(u)int, ptr(u)int or int(u)ptr types are ok.

2017-04-07 12:10 GMT-03:00 Michael Van Canneyt :

In Delphi, if i want an integer type which depends on the target platform (32 or 64 bits) i can use the NativeInt and NativeUInt types. What is the FPC standard type for this? PrtInt and PtrUInt? (I usually mix both delphi mode and objfpc mode units in the same project).

You can use PrtInt and PtrUInt for this or NativeInt and NativeUINT, they should be equivalent.

The only 'dubious' case may be the 8086 msdos case, which is somewhat confused about what exactly constitutes a pointer... There you may be better off with NativeInt and NativeUINT.

Michael.

2017-04-07 12:33 GMT-03:00 Michael Van Canneyt :

Thank you for the clarification.

Best regards

No. The only difference is that the smallest integer operation is 8 bit: On a 32 bit target, <byte>*<byte> is evaluated as a longint, on avr, it is evaluated as 8 bit operation.

However, we introduced ALUSInt/ALUUInt, it is an int type which scales with the ALU size of the CPU as PtrInt/PtrUInt are larger than the ALU on AVR.

but those are the general rules.