PRB: CLEAR ALL with Object References Causes Page Fault

Last reviewed: November 11, 1996
Article ID: Q158755

The information in this article applies to:

Microsoft Visual FoxPro for Windows, version 5.0

SYMPTOMS

If there are objects that reference each other, Visual FoxPro displays the following error message when CLEAR ALL is carried out:

   This Program has performed an illegal operation and will be shut down.

Visual FoxPro terminates due to an Invalid Page Fault.

WORKAROUND

Delete object references before carrying out CLEAR ALL.

STATUS

Microsoft has confirmed this to be a problem in the Microsoft products listed at the beginning of this article. We are researching this problem and will post new information here in the Microsoft Knowledge Base as it becomes available.

MORE INFORMATION

Steps to Reproduce Behavior

Create and run a program containing the following code:

      oform = CreateObject( "Form" )
      oform.AddObject("X", "CB")
      oform.AddObject("Y", "CB")
      oform.y.pointer=oform.x
      oform.x.pointer=oform.y
      CLEAR ALL  && This causes an Invalid Page Fault and
                 && shuts down Visual FoxPro.

      DEFINE CLASS CB as CommandButton
        pointer= .NULL.
      ENDDEFINE

Object references for "X" and "Y" above can be cleared by doing the following:

      oform.removeobject("X")
      oform.removeobject("Y")

KBCategory: kbprg kbenv kberrmsg kbprb
KBSubcategory: FxprgClassoop FxenvError
Additional reference words: 5.00 vfoxwin kbdsd

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Last reviewed: November 11, 1996
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