BUG: Changes to Double-Precision Values in Debugger Fail

 Last reviewed: March 8, 1996
Article ID: Q148202
The information in this article applies to: 

  - Microsoft Fortran PowerStation for Windows 95 and Windows NT,
    version 4.0

SYMPTOMS

When you change a single-precision number stored in a REAL*8 variable to a double-precision number in one of the debugger's watch windows, you will not be able to change the value again in the same debugging session. Furthermore, a REAL*8 variable that is initialized with a double-precision number cannot have its value changed in the debugger.

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. Build the following sample code in Developer Studio.

C Compile options needed: /Zi 

      real*8 DoubleVal1, DoubleVal2

      DoubleVal1 = 3.40E+38
      DoubleVal2 = 3.40D+40
      end

  • To invoke a debugging session in Developer Studio, click Debug on the Build menu, and then click Step Into.

  • In either the watch or quick watch window, type the variable names DoubleVal1 and DoubleVal2.

  • Change DoubleVal1 to a double-precision number by changing the exponent part to D+039 and pressing the ENTER key. Attempting to change the value of DoubleVal1 again in the current debugging session will not work. Attempting to change the value of DoubleVal2 after it has been initialized will fail.

    • Additional reference words: 4.00
    KBCategory: kbprg kbbuglist
    KBSubcategory: FORTLngIss

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    Last reviewed: March 8, 1996
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