PRB: L2028 Error Caused by HEAPSIZE, STACKSIZE and DGROUP Size

MS-DOS                                         | OS/2

The information in this article applies to:

• Microsoft LINK for MS-DOS, versions 5.01.21, 5.1, 5.13, 5.15, 5.3, 5.31.009, 5.5, and 5.6
• Microsoft LINK for OS/2, versions 5.01.21 and 5.1

SYMPTOMS

An attempt to link an application fails and Microsoft LINK displays the following message:

   L2028: Automatic data segment plus heap exceeds 64K

CAUSE

This error occurs when the segment containing the stack and data plus the near heap (DGROUP) exceeds 64K.

RESOLUTION

Use one of the following three methods to address this situation:

• Reduce the amount of data in the default data segment.

  If the L2028 error occurs with object modules produced by the Microsoft C compiler, one or more of the following three techniques will decrease the amount of data in the default data segment.

      = If the application uses the compact, large, or huge memory
        model, specify the /Gt3 compiler option switch to move any data
        item three bytes or larger from the default data segment
        (DGROUP) into a far data segment. If desired, you can specify a
        larger threshold.
  

      = Remove data from DGROUP by declaring it as FAR (in an
        application designed for the Microsoft Windows operating
        system), or far, _far, or __far depending on the version of
        Microsoft C, C/C++, or Visual C++ you are using.
  

      = If your application requires a large stack due to a great deal
        of local data (which is any non-static data declared in a
        function), declare that data as static to prevent it from being
        stored on the stack. Because this technique only moves the data
        to a different area in DGROUP, it must be combined with one of
        the techniques described earlier to remove it from DGROUP.
  

• Use the /ST linker option switch or the STACKSIZE option in the module definition (.DEF) file to reduce the size of the stack.
• Use the /CP linker option switch or the HEAPSIZE option in the .DEF file to reduce the amount of near heap space that the application requests. NOTE: this switch is only useful for building DOS applications. If you're building Windows applications, HEAPSIZE must be used.