How to debug in release mode?

Pedro picture Pedro · Jun 28, 2012 · Viewed 38.4k times · Source

I have to debug a c++ project, but as one dependency doesn't compile in debug mode and I haven't been able to fix that issue so far, I'd like to try to debug the project in release mode.

Currently the application crashes due to a null pointer, but I haven't the code that's causing the error. As break points apparently are ignored in release-mode, I'd like to know what's the best way find the error.

Answer

Ed S. picture Ed S. · Jun 28, 2012

In VS, right click your project, chose "Properties".

  1. Click the C/C++ node. Set Debug Information Format to C7 compatible (/Z7) or Program Database (/Zi).

  2. Expand Linker and click the General node. Set Enable Incremental Linking to No (/INCREMENTAL:NO).

  3. Select the Debugging node. Set Generate Debug Info to Yes (/DEBUG).

  4. Select the Optimization node. Set References to Yes (/OPT:REF).

    if /OPT:REF is specified, /OPT:ICF is on by default.

That's ripped directly from Microsoft's documentation:

I do this all of the time and pretty much never debug in debug mode anymore. As you know, many errors that occur in a release build may not occur in a debug build (almost certainly the errors that arise from invoking UB).

Also, I work on a project which uses a ton of image processing and performs a lot of compression/decompression of large images. Using a slow debug build is simply impractical.