Address of function in typeless pointer constant

[TCH]

I have a small program:

Code: Pascal  [Select][+][-]

1. program x;
2.  
3. function kecske(a: integer): integer; cdecl;
4. begin
5.         kecske := a + 8;
6. end;
7.  
8. var ptr: Pointer = Pointer(@kecske);
9.  
10. begin
11. end.

fpc x.pas

Code: [Select]

x.pas(8,36) Error: Illegal expressionIf i change the var to const, the result is identical. How can i store a function's address to a constant or an initialized variable as an untyped pointer?

[howardpc]

Code: Pascal  [Select][+][-]

1. program pointerEx;
2.  
3. {$mode objfpc}
4.  
5. function kecske(a: integer): integer; cdecl;
6. begin
7.   kecske := a + 8;
8. end;
9.  
10. var
11.   pKecske: Pointer = @kecske;
12.  
13. begin
14. end.

This compiles OK for me. 

[TCH]

Yeah, that worked for me too, but unfortunately it did not worked in my real case. My example program was incomplete. This was more like what i wanted to accomplish:

Code: Pascal  [Select][+][-]

1. program x;
2.  
3. type
4.         TProc = procedure; cdecl;
5.         TKecske = function (a: integer): integer; cdecl;
6.         PPointer = ^Pointer;
7.  
8. var Func: TProc;
9.  
10. function kecske(a: integer): integer; cdecl;
11. begin
12.         kecske := a + 8;
13. end;
14.  
15. const
16.         pKecske: Pointer = @kecske;
17.         pFunc: Pointer = @Func;
18.  
19. procedure set_it1(src: Pointer; dst: PPointer);
20. begin
21.         dst^ := src;
22. end;
23.  
24. begin
25.         set_it1(pKecske, @pFunc);
26.         WriteLn(TKecske(pFunc)(8));
27. end.

But in the meantime, i figured it out, the catch was casting the pointer to ppointer. Thanks for helping.

[howardpc]

I think it is generally better practice to use typed pointers, or if you have to use an untyped pointer cast it to the correct type:

Code: Pascal  [Select][+][-]

1. program pointerEx;
2.  
3. {$mode objfpc}
4.  
5. type
6.  
7.   TFunc = function(b: Integer): Integer; cdecl;
8.  
9. function kecske(a: integer): integer; cdecl;
10. begin
11.   kecske := a + 8;
12. end;
13.  
14. var
15.   pKecske: Pointer = @kecske;
16.  
17. begin
18.   WriteLn(TFunc(pKecske)(8);
19.   ReadLn;
20. end.

             

[TCH]

I have to work with different type of procedures and functions and store their addresses in a common list, so i only can store them as untyped pointers; usage is done with casting of course.