将FPC .o文件链接到Delphi

发布时间：2020-12-15 09:26:08 所属栏目：大数据来源：网络整理

导读：如何将FPC .o从库链接到Delphi可执行文件.当我尝试链接以下代码时,我得到了一堆不满意的前向或外部声明. library project1;{$mode objfpc}{$H+}uses Classes { you can add units after this };function Test: Integer;begin Result := -1;end;beginend.[dcc

如何将FPC .o从库链接到Delphi可执行文件.当我尝试链接以下代码时,我得到了一堆不满意的前向或外部声明.

library project1;

{$mode objfpc}{$H+}

uses
  Classes
  { you can add units after this };

function Test: Integer;
begin
  Result := -1;
end;

begin
end.


[dcc64 Error] Project2.dpr(170): E2065 Unsatisfied forward or external declaration: 'INIT$_$SYSTEM'
[dcc64 Error] Project2.dpr(170): E2065 Unsatisfied forward or external declaration: 'FINALIZE$_$OBJPAS'
[dcc64 Error] Project2.dpr(170): E2065 Unsatisfied forward or external declaration: 'INIT$_$LNFODWRF'
[dcc64 Error] Project2.dpr(170): E2065 Unsatisfied forward or external declaration: 'FINALIZE$_$LNFODWRF'
[dcc64 Error] Project2.dpr(170): E2065 Unsatisfied forward or external declaration: 'INIT$_$FPINTRES'
[dcc64 Error] Project2.dpr(170): E2065 Unsatisfied forward or external declaration: 'FINALIZE$_$WINDIRS'
[dcc64 Error] Project2.dpr(170): E2065 Unsatisfied forward or external declaration: 'SYSUTILS$_$TENCODING_$__$$_create'
[dcc64 Error] Project2.dpr(170): E2065 Unsatisfied forward or external declaration: 'SYSUTILS$_$TENCODING_$__$$_destroy'
[dcc64 Error] Project2.dpr(170): E2065 Unsatisfied forward or external declaration: 'INIT$_$SYSUTILS'
[dcc64 Error] Project2.dpr(170): E2065 Unsatisfied forward or external declaration: 'FINALIZE$_$SYSUTILS'
[dcc64 Error] Project2.dpr(170): E2065 Unsatisfied forward or external declaration: 'INIT$_$TYPINFO'
[dcc64 Error] Project2.dpr(170): E2065 Unsatisfied forward or external declaration: 'FINALIZE$_$TYPINFO'
[dcc64 Error] Project2.dpr(170): E2065 Unsatisfied forward or external declaration: 'INIT$_$CLASSES'
[dcc64 Error] Project2.dpr(170): E2065 Unsatisfied forward or external declaration: 'FINALIZE$_$CLASSES'
[dcc64 Error] Project2.dpr(170): E2065 Unsatisfied forward or external declaration: 'THREADVARLIST_$SYSTEM'
[dcc64 Error] Project2.dpr(170): E2065 Unsatisfied forward or external declaration: 'THREADVARLIST_$CLASSES'
[dcc64 Error] Project2.dpr(170): E2065 Unsatisfied forward or external declaration: 'RESSTR_$RTLCONSTS_$$_START'
[dcc64 Error] Project2.dpr(170): E2065 Unsatisfied forward or external declaration: 'RESSTR_$RTLCONSTS_$$_END'
[dcc64 Error] Project2.dpr(170): E2065 Unsatisfied forward or external declaration: 'RESSTR_$SYSCONST_$$_START'
[dcc64 Error] Project2.dpr(170): E2065 Unsatisfied forward or external declaration: 'RESSTR_$SYSCONST_$$_END'
[dcc64 Error] Project2.dpr(170): E2065 Unsatisfied forward or external declaration: 'FPC_LIBINITIALIZEUNITS'

解决方法

你不可能完成这项工作,至少是书面的.未满足的声明来自FPC运行时.您还需要链接它,或者在Delphi中重新实现它.这两种选择都不可行.

当然,如果你删除了对Classes单元的引用,并将这个简单的函数放在单独的代码单元而不是库单元中,那么可能没有不满意的声明是合理的.也就是说,你肯定在探索这个,因为你想使用实际做某事的FPC代码.一旦你这样做,那么你将立即回到原点.

解决此问题的方法是动态链接到FPC代码.将FPC代码编译到库中并动态链接到该库.

为了好玩,我试图将FPC对象链接到Delphi程序. FPC单位：

unit unit1;

interface

implementation

function Test(i: Integer): Integer; cdecl;
begin
  Test := i*42;
end;

end.

我编译了这个：

fpc unit1.pp

然后我编写了以下Delphi程序来链接它：

{$APPTYPE CONSOLE}

{$L 'unit1.o'}

function Test(i: Integer): Integer; cdecl; 
  external name 'UNIT1_TEST$SMALLINT$$SMALLINT';

begin
  Writeln(Test(666));
end.

输出：

请注意,函数名称已修饰.为了找到我用objdump的名字：

>objdump -d unit1.o

unit1.o:     file format pe-i386


Disassembly of section .text.n_unit1_test$smallint$$smallint:

00000000 :
   0:   55                      push   %ebp
   1:   89 e5                   mov    %esp,%ebp
   3:   83 ec 04                sub    $0x4,%esp
   6:   0f bf 45 08             movswl 0x8(%ebp),%eax
   a:   6b c0 2a                imul   $0x2a,%eax,%eax
   d:   66 89 45 fc             mov    %ax,-0x4(%ebp)
  11:   66 8b 45 fc             mov    -0x4(%ebp),%ax
  15:   c9                      leave
  16:   c3                      ret
        ...

我使用x86版本的编译器完成了这项工作.我希望它在x64下也可行.

所以你确实可以链接FPC对象文件,只要它们足够简单.但是,如果您需要任何FPC运行时和标准单元,那么我预计它会变得太难.

（编辑：李大同）

【声明】本站内容均来自网络，其相关言论仅代表作者个人观点，不代表本站立场。若无意侵犯到您的权利，请及时与联系站长删除相关内容!