Same old AIX problem

[Frédéric Poels <fpo@atos.be>]

Good afternoon!

OpenLDAP-2.0-alpha2 is not able to detect a thread library on AIX 4.2.1.
The small program configure relies on to test various threads
configurations is the following:

----- Code STARTS
#include "confdefs.h"
/* pthread test headers */
#include <pthread.h>
#ifndef NULL
#define NULL (void*)0
#endif

static void *task(p)
	void *p;
{
	return (void *) (p == NULL);
}


int main(argc, argv)
	int argc;
	char **argv;
{

	/* pthread test function */
	pthread_t t;
	int status;

	/* make sure pthread_create() isn't just a stub */
#if HAVE_PTHREADS_D4
	status = pthread_create(&t, pthread_attr_default, task, NULL);
#else
	status = pthread_create(&t, NULL, task, NULL);
#endif

	if( status ) exit( status );

	/* make sure pthread_detach() isn't just a stub */
#if HAVE_PTHREADS_D4
	status = pthread_detach( &t );
#else
	status = pthread_detach( t );
#endif

#ifdef HAVE_LINUX_THREADS
	pthread_kill_other_threads_np();
#endif

	exit( status );

}
----- Code ENDS

Here's what happens:
...
-> HAVE_PTHREADS_D4 is not defined
status = pthread_create(&t, NULL, task, NULL);
-> OK status is 0 but as a default, threads are created DETACHED on AIX (!!!)
...
-> HAVE_PTHREADS_D4 is not defined
status = pthread_create(&t, NULL, task, NULL);
-> KAWABUNGA! status is 3!

Here's the code that should be used instead (I think it's more portable
even on <beeeeeep> OS'es like AIX):

----- Code STARTS
#include "confdefs.h"
/* pthread test headers */
#include <pthread.h>
#ifndef NULL
#define NULL (void*)0
#endif

static void *task(p)
	void *p;
{
	return (void *) (p == NULL);
}


int main(argc, argv)
	int argc;
	char **argv;
{

	/* pthread test function */
	pthread_t t;
	pthread_attr_t attr;
	int status;

	/* set explicit default */
	status = pthread_attr_init( &attr );
	if( status ) exit( status );
#ifdef PTHREAD_CREATE_JOINABLE
	status = pthread_attr_setdetachstate( &attr, PTHREAD_CREATE_JOINABLE );
#else
	status = pthread_attr_setdetachstate( &attr, PTHREAD_CREATE_UNDETACHED );
#endif
	if( status ) exit( status );
	/* some more default values could be set here */
	/* an explicit default could also be set for pthread_attr_default ? */

	/* make sure pthread_create() isn't just a stub */
#if HAVE_PTHREADS_D4
	status = pthread_create(&t, pthread_attr_default, task, NULL);
#else
	status = pthread_create(&t, &attr, task, NULL);
#endif

	if( status ) exit( status );

	/* make sure pthread_detach() isn't just a stub */
#if HAVE_PTHREADS_D4
	status = pthread_detach( &t );
#else
	status = pthread_detach( t );
#endif

#ifdef HAVE_LINUX_THREADS
	pthread_kill_other_threads_np();
#endif

	exit( status );

}
----- Code ENDS

Note that the same code should be used in thr_posix.c.

Ciya,

Frederic Poels.