#3771 apache and websh


Tcl 8.4.15
Windows 2003 Service Pack 1
Apache: 2.2.4
Tcl: 8.4.15
Websh: Websh 3.6.b4 (2006-03-05)

I have a simple test that bring the server time and date the page is refreshed every 3 second (just testing).

After opening 20 pages the web server is crash.

[Sun Aug 26 13:33:25 2007] [notice] Child 448: Starting thread to
listen on port 2080.
alloc: invalid block: 008ED5B0: f8 0 0

This application has requested the Runtime to terminate it in an
unusual way.
Please contact the application's support team for more information.
[Sun Aug 26 13:37:11 2007] [crit] Parent: child process exited with
status 3 -- Aborting.


  • miguel sofer

    miguel sofer - 2007-08-28

    Logged In: YES
    Originator: NO

    This seems to be the issue discussed on clt at

    There it is reported that the failure occurs with both 8.4.15 with
    alloc: invalid block: 008ED5B0: f8 0 0
    and under 8.5 (version 8.5b8??) with
    TclStackFree: incorrect freePtr. Call out of sequence?
    It is reported that the crash occurs under Win2003, but not with XP.

    This looks like a buffer overrun (someone stomping over allocation block info, either zippy's or TclStackAlloc's). But it could be mem corruption of some other type, or who knows what.

    Not much chance to progress without a stack trace - not even to determine if this is a websh or tclsh problem. Any other suspects around - ie, binary extensions loaded? Requesting further assistance from reporter on clt

  • miguel sofer

    miguel sofer - 2007-08-28
    • labels: --> 41. Memory Allocation
  • zacky azoulay

    zacky azoulay - 2007-08-29

    Logged In: YES
    Originator: NO


    I don't know if this is relative but I got the following results:

    I compile tcl 8.4.15 on windows xp and 2003 run the Tcl's

    Window XP Service Pack 2
    Tcl 8.4.15
    Compile and Test are ok
    Tests ended at Mon Aug 27 09:05:14 Jerusalem Daylight Time 2007
    all.tcl: Total 10920 Passed 10139 Skipped 781
    Failed 0

    Windows 2003 Service Pack 1
    Tcl 8.4.15
    Compile Pass
    Test Failed


    ==== httpold-4.12 httpEvent FAILED
    ==== Contents of test case:

    set x {}
    after 500 {lappend x ok}
    set token [http_get $url -timeout 1 -command {lappend x fail}]
    vwait x
    list [http_status $token] $x

    ---- Result was:
    ok ok
    ---- Result should have been (exact matching):
    timeout ok
    ==== httpold-4.12 FAILED

    Tests ended at Mon Aug 27 11:42:05 AM Jerusalem Daylight Time 2007
    all.tcl: Total 10920 Passed 10145 Skipped 774
    Failed 1

    I run also run the httpold.test test 20 time with the same result
    Windows xp 20 pass
    Windows 2003 20 fail

    I copy 2003 compilation result to XP run the httpold.test test and it
    I copy XP compilation result to 2003 run the httpold.test test and it

    Regards Zacky

  • Ronnie Brunner

    Ronnie Brunner - 2007-09-04

    Logged In: YES
    Originator: NO

    I found a potential problem in Websh on Server 2003 (don't ask me why it should be different on that platform...)

    Is the following code correct (it's Websh code, not Tcl code)?

    Tcl_Obj *tmp = NULL;
    tmp = Tcl_NewStringObj(source, length);
    var = Tcl_ObjSetVar2(interp, varname,


    Note that there is no Tcl_IncrRefCount(tmp) before the call to Tcl_ObjSetVar2(). I thought this should work, but it crashes on Win Server 2003...

    If I indeed need to fix this, I'll send a patched version to the OP (assuming it was zackya) so he can check if the error still occurs.

    Please advise...

  • miguel sofer

    miguel sofer - 2007-09-04
    • status: open --> pending-invalid
  • miguel sofer

    miguel sofer - 2007-09-04

    Logged In: YES
    Originator: NO

    No, that is wrong: you should Tcl_IncrRefCount(tmp) before calling Tcl_ObjSetVar2(). See http://wiki.tcl.tk/14880 for guidance on these issues.

    Why the problem is only apparent on Server 2003: a mystery. It is always wrong, $varname will be just about anything after this: the obj has been freed, it will be reused for something else (assuming a standard Tcl compilation).

    [*] If the refCount is not incr/decr, Tcl (pre 8.5, not anymore in HEAD) will leak the Tcl_Obj whenever a variable called 'varname' cannot be set - for instance, if it refers to a non-existing namespace.

  • SourceForge Robot

    • status: pending-invalid --> closed-invalid
  • SourceForge Robot

    Logged In: YES
    Originator: NO

    This Tracker item was closed automatically by the system. It was
    previously set to a Pending status, and the original submitter
    did not respond within 14 days (the time period specified by
    the administrator of this Tracker).