Unable to use C's .OBJ files compiled by cl.exe in Delphi XE4 Win64 platform

Question

I want to translate 7Zip's SDK to Delphi/Pascal's unit file. First, I try compile the C files using BCC32.exe for Win32 platform:

bcc32.exe -c -D_LZMA_PROB32 -D_WIN32 -v -y Threads.c LzFind.c LzFindMt.c LzmaDec.c LzmaEnc.c

It produces few .OBJ files and I am able to use these objects in Delphi units without problem.

unit Threads;

interface

uses System.Win.Crtl, Winapi.Windows, LzmaTypes, System.Classes;

{$Z4}
type
  TCEvent = THandle;

  TCSemaphore = THandle;

  TCCriticalSection = TRTLCriticalSection;

  TCAutoResetEvent = TCEvent;

  TCThread = THandle;

  TThread_Func_Type = Pointer;

function __beginthreadex(__security_attr: Pointer; __stksize: Cardinal; __start:
    TThread_Func_Type; __arg: Pointer; __create_flags: Cardinal; var
    __thread_id: Cardinal): Cardinal; cdecl; external msvcrt name _PU +
    '_beginthreadex';

function _Event_Reset(var p: TCEvent): TWRes; cdecl; external name _PU +
    'Event_Reset';

function _Event_Set(var p: TCEvent): TWRes; cdecl; external name _PU +
    'Event_Set';

function _Handle_WaitObject(h: THandle): TWRes; cdecl; external name _PU +
    'Handle_WaitObject';

function _Semaphore_Release1(var p: TCSemaphore): TWRes; cdecl; external name
    _PU + 'Semaphore_Release1';

function _HandlePtr_Close(var h: THandle): TWRes; cdecl; external name _PU +
    'HandlePtr_Close';

function _CriticalSection_Init(var p: TCCriticalSection): TWRes; cdecl; external
    name _PU + 'CriticalSection_Init';

function _AutoResetEvent_CreateNotSignaled(var p: TCAutoResetEvent): TWRes;
    cdecl; external name _PU + 'AutoResetEvent_CreateNotSignaled';

function _Semaphore_Create(var p: TCSemaphore; initCount: UInt32; maxCount:
    UInt32): TWRes; cdecl; external name _PU + 'Semaphore_Create';

function _Thread_Create(var p: TCThread; func: TThread_Func_Type; param:
    LPVOID): TWRes; cdecl; external name _PU + 'Thread_Create';

implementation

{$ifdef Win64}
  {$L Win64\Threads.o}
{$else}
  {$L Win32\Threads.obj}
{$endif}

end.

I then attempt to compile these object files using BCC64.exe for Win64 platform:

bcc64.exe -c -D_LZMA_PROB32 -D_WIN64 -v -y Threads.c LzFind.c LzFindMt.c LzmaDec.c LzmaEnc.c

This time, it produces few .o files but I get errors when compile the Delphi unit:

[dcc64 Fatal Error] LzFind.pas(128): F2084 Internal Error: AV0756F5D3-R2D06DB90-0

I learned that the object file format recognized for Delphi Win64 is 64 bit COFF whereas BCC64.exe produces ELF64 format.

I then try to use cl.exe from Microsoft Windows SDK to produce both Win32 and Win64 .OBJ files,

cl.exe -c -D_LZMA_PROB32 -D_WIN32 Threads.c LzFind.c LzFindMt.c LzmaDec.c LzmaEnc.c

x86_amd64\cl.exe -c -D_LZMA_PROB32 -D_WIN64 Threads.c LzFind.c LzFindMt.c LzmaDec.c LzmaEnc.c

but I get these errors:

[dcc32 Error] Threads.pas(64): E2065 Unsatisfied forward or external declaration: '__imp__CloseHandle@4'
[dcc32 Error] Threads.pas(64): E2065 Unsatisfied forward or external declaration: '__imp__GetLastError@0'
[dcc32 Error] Threads.pas(64): E2065 Unsatisfied forward or external declaration: '__imp__InitializeCriticalSection@4'

Any ideas how to use cl.exe to produce .OBJ files that may compiled by Delphi unit in both Win32 and Win64 platform?

Answer 1

It is a bit confusing, but in Delphi,

• for 64 bit, you can use 64 bit COFF files as produced by, for instance, Microsoft's 64 bit compiler. Delphi XE6 64 bit is reportedly capable of linking with 64 bit ELF files too, as C++Builder 64 bit produces them.

• for 32 bit, you can use 32 bit OMF C object files, as produced by C++Builder. Delphi XE2 and newer (see this link from David Heffernan's comment) allow you to link to 32 bit COFF too.

Some more info on the subject: Using C object files in Delphi

So since Delphi XE6, you can actually use C++Builder to generate Delphi-linkable object files for both platforms again.