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Q149154: BUG: Memory Leak Caused by Formatted Internal WRITE

Article: Q149154
Product(s): Microsoft Fortran Compiler
Version(s): 4.0
Operating System(s): 
Keyword(s): kbFortranPS kbLangFortrankbbuglist
Last Modified: 02-NOV-1999

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The information in this article applies to:

- Microsoft Fortran PowerStation for Windows 95 and Windows NT, version 4.0 
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SYMPTOMS
========

Performing a formatted internal WRITE causes a memory leak. A memory leak is
caused by a program not releasing the memory it allocates.

RESOLUTION
==========

Use list-directed I/O with an internal WRITE.

STATUS
======

Microsoft has confirmed this to be a bug 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
================

In the following sample code, the memory storage area associated with the
character string "LLINE" is not released after each internal WRITE.
Consequently, additional memory must be allocated for each subsequent internal
WRITE utimately causing all physical and virtual memory to be exhausted.

Sample Code to Illustrate Problem and Workaround
------------------------------------------------

  ! Compile options needed: none

        PROGRAM TEST
        INTEGER I
        CHARACTER LLINE*32
        DO I=1,1000000
            WRITE(LLINE, '(I10,E20.5)') I, REAL(I) ! Memory leak here
  !          WRITE(LLINE, *) I, REAL(I) ! Uncomment this line for workaround
        END DO
        END

Additional query words: 4.00

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Keywords          : kbFortranPS kbLangFortran kbbuglist
Technology        : kbAudDeveloper kbPTProdChange kbFortranSearch kbFORTRANPower400NT
Version           : :4.0

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