FIX: Visual C++ Debugger Crashes on Very Long Symbols

• Microsoft Visual C++, 32-bit Edition, version 4.2

SYMPTOMS

When you place the caret on a line that contains a very long symbol name while you are debugging an application using Visual C++ in disassembly view, the debugger may crash.

A possible error message is:

   “MSDEV caused an invalid page fault in module <unknown> at
   00de:676e6972”

CAUSE

This behavior occurs because the debugger currently has a limit of 255 characters for symbols.

RESOLUTION

1. Do not use the disassembly view to step through sections of code where very long symbol names are present.

   -or-

2. Do not let the caret land on a line with a very long symbol name. Use the mouse to place the caret on a line following the one with the long symbol name, and select Run to Cursor from the Debug menu.

   -or-

3. Reduce the size of the mangled symbol names. You can do this by shortening the names of classes and class members. You can also shorten class names of classes that you have not written by using a

      #define before the #include for the header declaring the class. If the
      class name is basic_string and you want to shorten it to BS, then
      insert "#define basic_string BS" before the #include for the header
      declaring basic_string.
   
   

STATUS

Microsoft has confirmed this to be a bug in the Microsoft products listed at the beginning of this article. This bug was corrected in Visual C++ version 5.0. The limit is now (256+128).

REFERENCES

Sample Code

      /* Compile options needed: /GX
      */

      #pragma warning(disable:4786)
      #include <string>
      #include <map>
      struct ThreeString
      {
          string s1,s2,s3;
          ThreeString(string i1,string i2,string i3) {
              s1 = i1;
              s2 = i2;
              s3 = i3;
          }
          ThreeString() {}
      };
      typedef map<string, ThreeString, less<string>,
      allocator<ThreeString> > MapType;

      void main()
      {
          MapType themap;

          themap["Zero"] = ThreeString("Zero","Zero","Zero");
          themap["One"] = ThreeString("One","One","One");
      }

Keywords          : vcfixlist500 WBDebug
Version           : 4.2
Platform          : NT WINDOWS
Issue type        : kbbug
Solution Type     : kbfix