DOCUMENT:Q125468 03-NOV-1999 [fortran] TITLE :PRB: F6700 Heap Space Exceeded PRODUCT :Microsoft Fortran Compiler PROD/VER::5.1 OPER/SYS: KEYWORDS: ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft FORTRAN Compiler for MS-DOS, version 5.1 ------------------------------------------------------------------------------- SYMPTOMS ======== When you run a QuickWin program and try to allocate a huge array dynamically, the return code may be 6700. The associated error message, as documented in the FORTRAN Professional Development System on page 489, is: F6700 heap space limit exceeded CAUSE ===== One cause of the error may be attempting to allocate a huge array (greater than 64K) where the data items do not align on 64K segment boundaries. RESOLUTION ========== Change the data type such that the array will align on the 64K boundary. STATUS ====== This behavior is by design. MORE INFORMATION ================ If you attempt to dimension the huge array statically, the compiler produces this error: F2120 : : huge array cannot be aligned to segment boundary Compiling and running the following code sample produces an output for 'istat' of 6700, indicating the heap space was exceeded and no dynamic memory was allocated. If you change the line declaring the array 'str' as allocatable into a comment, and change the static declaration from a comment into an excuted line, the compiler produces the F2120 error. Changing the declaration to: CHARACTER*16 str(10, 6400) eliminates the error in both cases. Sample Code ----------- /* Compile options needed: /MW */ PROGRAM testmem C QuickWin application so we can use more than 640K C C Create an allocatable array over 64K CHARACTER*12 str[ALLOCATABLE, HUGE](:,:) C Creating the array statically produces the F2120 error C CHARACTER*12 str(10, 6400) INTEGER istat C The allocate should fail with error 2120 C since a single string crosses a segment boundary C but instead produces an error 6700 C indicating heap space limit exceeded ALLOCATE(str(10, 6400), stat=istat) PRINT*, "Error code (0 is success) = ", istat IF(istat .eq. 0) THEN DEALLOCATE(str) END IF END Additional query words: 5.10 fail memory allocation ====================================================================== Keywords : Technology : kbAudDeveloper kbFortranSearch kbZNotKeyword3 kbFORTRAN510DOS Version : :5.1 ============================================================================= THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY. Copyright Microsoft Corporation 1999.