Q148383: BUG: INTENT(OUT) Allows Subroutine to Use Undefined Argument

Article: Q148383
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
========

An illegal use of a dummy variable specified by the INTENT(OUT) statement does
not cause an appropriate compile-time error or warning message to be generated.

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
================

The INTENT(OUT) dummy argument must be defined by the subroutine before it is
used. When the subroutine is started, the dummy argument is undefined, so any
executable statement associated with it prior to its definition should cause a
compilation error or warning.

Sample Code to Illustrate Problem
---------------------------------

  C Compile options needed: none

        real z
        z = 32
        call sub(z)
        print *, z
        end

        subroutine sub(x)
        real, intent(out) :: x
        print *, x   ! x undefined; No compiler warning or error generated
        X = 5
        end subroutine

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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