in reply to Re^4: XS: free() outside of the main thread causes crash on Windows
in thread XS: free() outside of the main thread causes crash on Windows

If you do this on win32 I don't get this "double free" error 
#include <pthread.h>

void *thread(void *arg) {
    char *msg = (char*)arg;
    printf("thread: %s\n", msg);
    free(msg);
    return NULL;
}

#include "EXTERN.h"
...

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Re^6: XS: free() outside of the main thread causes crash on Windows
by OlegG (Monk) on Sep 25, 2014 at 08:27 UTC
    And gdb output looks not very usefull
    (gdb) r t.pl
Starting program: C:\Perl64\bin\perl.exe t.pl
[New Thread 17748.0x6114]
[New Thread 17748.0x61f8]
thread: Just another XS hacker
warning: Critical error detected c0000374


Program received signal SIGTRAP, Trace/breakpoint trap.
[Switching to Thread 17748.0x61f8]
0x00000000770d40d0 in ntdll!RtlUnhandledExceptionFilter ()
   from C:\WINDOWS\SYSTEM32\ntdll.dll
(gdb) bt
#0  0x00000000770d40d0 in ntdll!RtlUnhandledExceptionFilter ()
   from C:\WINDOWS\SYSTEM32\ntdll.dll
#1  0x00000000770d4746 in ntdll!EtwEnumerateProcessRegGuids ()
   from C:\WINDOWS\SYSTEM32\ntdll.dll
#2  0x00000000770d5952 in ntdll!RtlQueryProcessLockInformation ()
   from C:\WINDOWS\SYSTEM32\ntdll.dll
#3  0x00000000770d7604 in ntdll!RtlLogStackBackTrace ()
   from C:\WINDOWS\SYSTEM32\ntdll.dll
#4  0x000000007707dc47 in ntdll!RtlIsDosDeviceName_U ()
   from C:\WINDOWS\SYSTEM32\ntdll.dll
Backtrace stopped: previous frame inner to this frame (corrupt stack?)
(gdb)

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Re^6: XS: free() outside of the main thread causes crash on Windows
by OlegG (Monk) on Sep 25, 2014 at 08:19 UTC
    I changed it to
    #include <pthread.h>

void *thread(void *arg) {
    char *msg = (char*)arg;
    printf("thread: %s\n", msg);
    free(msg);
    return NULL;
}

#include "EXTERN.h"
#include "perl.h"
#include "XSUB.h"
#include "ppport.h"

MODULE = My    PACKAGE = My

void
test_thread(char *msg)
    PPCODE:
        char *thread_arg = malloc((strlen(msg)+1)*sizeof(char));
        strcpy(thread_arg, msg);
        pthread_t tid;
        pthread_create(&tid, NULL, thread, (void*)thread_arg);
        
        void *rv;
        pthread_join(tid, &rv);

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    And the problem still here: crash on each run
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[d/l]

      And the problem still here: crash on each run

      No problem for me I got citrusperl 5.16.1 with 

      $ gcc --version
gcc (gcc-4.6.3 release with patches [build 20121012 by perlmingw.sf.ne
+t]) 4.6.3
Copyright (C) 2011 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There i
+s NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PUR
+POSE.

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[d/l]
        I am testing on ActiveState perl
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