Enable Guard Bytes
Guard Bytes is a LabVIEW diagnostic feature that inserts known byte patterns before and after each memory allocation. LabVIEW validates these patterns during memory resize and deallocation. If the guard regions are overwritten, LabVIEW will immediately crash and generate a dump file to help pinpoint the corruption.
To enable Guard Bytes on Windows:
- Open Start → search for Environment Variables.
- Select Edit the system environment variables → Environment Variables…
- Under System variables, click New…
- Enter:
- Variable name: LVGuardBytes
- Variable value: check
- Save and restart the system to ensure all processes detect the change.
Use Alternate Memory Manager
Add LV_USE_MALLOC=1 to LabVIEW's command line. This will cause it to load a different version of our mgcore dll that contains our memory manager (multiple versions are included in the shipping resource directory). The default is smartheap but this option uses the C malloc/free instead. Since these memory managers use different data structures and allocation schemes, switching can impact how memory corruptions expose themselves and may provide more context to determine where the corruption happened.
The command to be used with LabVIEW 64-bit is
"C:\Program Files\National Instruments\LabVIEW <YYYY>\LabVIEW.exe" -- LV_USE_MALLOC=1
and for LabVIEW 32-bit
"C:\Program Files (x86)\National Instruments\LabVIEW <YYYY>\LabVIEW.exe" -- LV_USE_MALLOC=1
where <YYYY> is the year of your current LabVIEW.