Hi,

Here is the Inline::C demo, based on the wikipedia example program. It runs fine for me on Cygwin, but never gets beyond the malloc call on native Win32 - where I'm using perl-5.12.0 and mingw.org's port of gcc-4.5.2 (which ships with the pthread library included).

Note that I'm allocating with 'malloc'. Re-allocating with 'realloc' produces the same problem, as does using 'Newx' or 'Renew' instead of the standard C functions.

use warnings;
use Inline C => Config =>
    LIBS => '-lpthread',
    BUILD_NOISY => 1;

use Inline C => <<'EOC';

#include <pthread.h>
#include <stdio.h>
#include <stdlib.h>
#include <assert.h>
#include <malloc.h>

void *TaskCode(void *argument) {
   int tid;
   char * s;

   tid = *((int *) argument);

   printf("thread %d: calling malloc\n", tid);
   s = (char*) malloc(100);
   printf("thread %d:  malloc called\n", tid);

   return NULL;
}

void demo (int NUM_THREADS) {

   pthread_t threads[NUM_THREADS];
   int thread_args[NUM_THREADS];
   int rc, i;

   /* create all threads */
   for (i=0; i<NUM_THREADS; ++i) {
      thread_args[i] = i;
      printf("In demo: creating thread %d\n", i);
      rc = pthread_create(&threads[i], NULL, TaskCode, (void *) &threa
+d_args[i]);
      assert(0 == rc);
   }
 
   /* wait for all threads to complete */
   for (i=0; i<NUM_THREADS; ++i) {
      rc = pthread_join(threads[i], NULL);
      assert(0 == rc);
   }
 
   exit(EXIT_SUCCESS);
}

EOC

demo(2);
[download]

As is, on Win32 that outputs:

In demo: creating thread 0
In demo: creating thread 1
thread 0: calling malloc
thread 1: calling malloc
[download]

at which point it crashes. (Irrespective of how many threads I specify it always crashes when *all* threads have reached the stage of having to allocate the memory.)

If I comment out the s = (char*) malloc(100); it outputs the expected:

In demo: creating thread 0
In demo: creating thread 1
thread 0: calling malloc
thread 0:  malloc called
thread 1: calling malloc
thread 1:  malloc called
[download]

Does anyone have some advice as to how I might successfully allocate memory inside the 'TaskCode' function on Win32 ?

(I'm also interested to hear any theories that explain the behaviour I'm seeing.)

Cheers,
Rob

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