DOCUMENT:Q145821 03-AUG-2001 [visualc] TITLE :BUG: Format Specifications Give Incorrect Output PRODUCT :Microsoft C Compiler PROD/VER:MACINTOSH:4.0 OPER/SYS: KEYWORDS:kbCRT kbVCkbbuglist ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft Visual C++, Macintosh Cross-Development Addon, version 4.0, on platform(s): - the operating system: Mac OS (all) ------------------------------------------------------------------------------- SYMPTOMS ======== When you use the C run-time functions such as sprintf when building a 68K Macintosh target, the format specification for long double (%ld, %le, %lg) yields incorrect output. This is not a problem with a Power Macintosh target. RESOLUTION ========== Use other format specifications. Internally, do your calculations using long doubles. However, when it comes time to output final results, convert the result to a double, and use the corresponding format specification. 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 ================ Code to Reproduce Problem ------------------------- /* Compile options needed: default */ char buf[1000]; long double ldReturn = 7.9718893639526417; sprintf(buf,"ldReturn(%%ld)=%ld\n", ldReturn); /* Instead, do the following */ char buf[1000]; long double ldReturn = 7.9718893639526417; sprintf(buf,"ldReturn(%%d)=%ld\n", (double)ldReturn); Additional query words: 4.00 Windows 95 NT ====================================================================== Keywords : kbCRT kbVC kbbuglist Technology : kbVCsearch kbHWMAC kbOSMAC kbAudDeveloper Version : MACINTOSH:4.0 ============================================================================= 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 2001.