CVPACK May Lose Type Information in Large Files

ID Number: Q58718

2.01 3.01 | 2.01 3.01

MS-DOS | OS/2

Summary:

Certain type information such as that required to expand a structure

using the "?? <structurename>" command in CodeView can be lost in

large files when using CVPACK.

More Information:

Running CVPACK on very large executables may remove such information

from the file. Before running CVPACK, internal information can be

viewed and members can be expanded on structures; after CVPACK, only

the structure's address is viewable.

The reason this occurs is that CVPACK is stripping out information

that CodeView needs to correctly display pointers to far data.

In this case, CodeView attempts to provide information on the pointers

to far data in the structure, but the information it gives is not

correct. Observing the change in the structure's segment address

before and after using CVPACK shows that this address changes while

the offset address remains the same. Therefore, the correct

information cannot be displayed, and CodeView emits a warning beep

instead of showing the expanded structure elements.