Q149751: BUG: FOR3294 Error Using Module Inside Module Procedure

Article: Q149751
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
========

Referencing a user-defined data type, defined in one module, at another module's
internal procedure level causes the compiler to fail to recognize the
user-defined data type. Specifically, this occurs when the module and main
program sources are contained in different files. The following compiler error
is generated under these circumstances:

  error FOR3294: derived type referenced but not declared

RESOLUTION
==========

Do one of the following:

- Use the module containing the user-defined data type at the module level, not
  at the module's internal procedure level.

-or-

- Combine the module and program source code into one source file.

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

Steps to Reproduce Problem
--------------------------

1. Using the sample code provided, create a module and program file.

2. Compile and link the module and program files together.

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

  ! Compile options needed: none

  ! --- mods.for ---

        module types
          type my_type
              real :: x
          end type my_type
        end module types

        module funcs
  !     use types               ! uncomment this line for first workaround
        contains
          function my_func(z1) result(z2)
              use types         ! comment this line for first workaround
              implicit none
              real z1
              type(my_type) z2
              z2 % x = z1
          end function my_func
        end module funcs

  ! --- prog.for ---

        program test
          use types
          use funcs
          implicit none
          real a
          type (my_type) :: b

          a = 1.0
          b = my_func(a)
        end program test

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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