I've got some troubles with pthread_cond_init when calling it in class members. After this action next calling of class constructor for second object bring to SIGSEGV. When I tried to use Object instead Class all seems fine, but for my task Object not approach. What it can be?

program pthcondtest;
{$mode objfpc}{$H+}
uses
  pthreads;
type
TCondv = class
   CAttr : pthread_condattr_t;
   Cond : pthread_cond_t;
public
  constructor Create;
  destructor Destroy; override;
end;
{TCondv}
constructor TCondv.Create;
begin
  pthread_condattr_init(CAttr);
  pthread_cond_init(Cond, CAttr);
end;
destructor TCondv.Destroy;
begin
  inherited;
  pthread_cond_destroy(Cond);
  pthread_condattr_destroy(CAttr);
end;
{TCondv}
var
  obj1 : TCondv;
  obj2 : TCondv;
begin
  obj1 := TCondv.Create;
  obj2 := TCondv.Create;
  obj1.Destroy;
  obj2.Destroy;
end.

I never used pthreads, but looking at the constructor of TCondv, it seems to require CAttr and Conv to be setted before calling pthread_condattr_init and pthread_cond_init.

Leonardo M. Ramé
http://leonardorame.blogspot.com

__________________________________________________ Do You Yahoo!?
Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com

No, pthread_condattr_init and pthread_cond_init initialize variables CAttr and Cond. By the by, this code written in C work right.

2007/5/7, Leonardo M. Ramé :

Can this error caused by wrong work of fpc compiler or linker?

Артем Смирнов wrote

I've got some troubles with pthread_cond_init when calling it in class members. After this action next calling of class constructor for second object bring to SIGSEGV. When I tried to use Object instead Class all seems fine, but for my task Object not approach. What it can be?

Please specify your OS and FreePascal version. Your program works fine on my config (FPC 2.0.4, Debian Sarge, libc6 package version 2.3.2.ds1-22sarge6 (pthreads is part of the libc6 package)).

Bram

fpc 2.0.4, opensuse 10.2, glibc-2.4-31.1

2007/5/7, Bram Kuijvenhoven :

> fpc 2.0.4, opensuse 10.2, glibc-2.4-31.1

You may try this version of your program
-----
program Project1;

{$mode objfpc}{$H+}
uses
 UnixType,pthreads;
type
TCondv = class
private
   Cond : UnixType.pthread_cond_t;
   CAttr : UnixType.pthread_condattr_t;
public
  constructor Create;
  destructor Destroy; override;
end;
{TCondv}
constructor TCondv.Create;
begin
  pthread_condattr_init(@CAttr);
  pthread_cond_init(@Cond, @CAttr);
end;
destructor TCondv.Destroy;
begin
  inherited;
  pthread_cond_destroy(@Cond);
  pthread_condattr_destroy(@CAttr);
end;
{TCondv}
var
  obj1 : TCondv;
  obj2 : TCondv;
begin
  obj1 := TCondv.Create;
  obj2 := TCondv.Create;
  obj1.Destroy;
  obj2.Destroy;
end.
---------------

I had bad experiences with types differently declared in pthreads and UnixTypes.
Namely the following:

In pthread:

  pthread_cond_t = record
    __c_lock: _pthread_fastlock;
    __c_waiting: _pthread_descr;
  end;

In UnixType: (ptypes.inc)

  pthread_cond_t = record
    __c_lock: _pthread_fastlock;
    __c_waiting: pointer;
    __padding:
array[0..48-1-sizeof(_pthread_fastlock)-sizeof(pointer)-sizeof(clonglong
)] of byte;
    __align: clonglong;
  end;
A call like: i:=pthread_cond_timedwait(@FSignal, @MMutex,@tim);
Fails with the first version (EINVAL), but succedes with the second one.

HTH,
helmut

I wonder if this might be a useful read to the architects here.

http://weblogs.mozillazine.org/roc/archives/2007/04/history_based_s.html

Yeah, this one work correctly. Thanks!

2007/5/8, Helmut Hartl :