1. Create a new Qt Widgets Application project.
2. Configure it with kits using Qt 4.8.7 and Qt 5.5.1.
3. Select the "Profile" build configuration of the Qt 4.8 kit.
4. Build this with MSVC and run it in cdb.
   Creator will warn that you are not using a "Debug" build:
   
5. Select the "Profile" build configuration of the Qt 5.5 kit.
6. Build this with MSVC and run it in cdb.
   Creator will not warn.

Creator should behave in the same way. I think it should warn in both cases.

Found by Squish test tst_cli_output_console.