[fpc-devel] how to get same pthreads code to compile between Linux and FreeBSD

[Graeme Geldenhuys]

On 2013-02-03 12:28, Sven Barth wrote:
> 
> I personally think that the fpc-pascal list was the more approbiate, but 
> nevertheless: your problem comes down to this code (in principal):

I thinking was that this problem seems to point towards a bug, or at
least inconsistency between defined types and various platforms. But as
you say, nevertheless.  Thanks for replying.

> 
> type
>    sem_t_rec = record
>    end; // from rtl/freebsd/ptypes.inc
>    sem_t = ^sem_t_rec; // from rtl/freebsd/ptypes.inc
>    psem_t = ^sem_t; // from packages/pthreads/src/pthrbsd.inc


Indeed, the sem_t is differently defined between Linux and FreeBSD.
Under Linux, sem_t is just a record defined as:

  // rtl/linux/ptypes.inc
  sem_t = record
     __sem_lock: _pthread_fastlock;
     __sem_value: cint;
     __sem_waiting: pointer;
  end;

In FreeBSD sem_t is pointer. Isn't that what psem_t is for? So under
FreeBSD sem_t should be defined as

  sem_t_rec = record
  end;
  sem_t = sem_t_rec;
  psem_t = ^sem_t;



I would expect unix-types / posix-types supposed to be defined the same
in all such related OSes (eg: *BSD, Linux, MacOSX, Haiku, *nix)?


> Now the problem is the "@s". This returns type "Pointer" and now you 
> have two pointer types: sem_t and psem_t. Thus the compiler can not 
> resolve this.

Indeed. You just seem to have explained it better than I.



Regards,
  - Graeme -

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