Buttonless DFU service does not start when NRF_LOG_ENABLED is set 0

[AntonHellbe]

Hi all,

I have a very strange problem with the Buttonless DFU service. For my project we have two different builds, one debug and one "release" build. The debug build sets the following SDK config defines to 1, and the release build sets them to 0.

• NRF_SDH_BLE_LOG_ENABLED
• NRF_SDH_SOC_LOG_ENABLED
• NRF_SDH_LOG_ENABLED
• NRF_LOG_BACKEND_RTT_ENABLED
• NRF_LOG_ENABLED

When I compile the project and flash the debug build (application + softdevice + bootloader) the application starts up and I can access the DFU service. However when I compile and flash the "release" build the application does not start. If I remove the DFU service the application starts up with both builds, so there's something happening when I disable the logs with the DFU service. Its very hard to debug since everything works the logs are enabled.

I've had some issues before with observers being optimized way since the source code from the libs is not being directly referenced from my code. Could it be something similar going on here? https://devzone.nordicsemi.com/support/224969 (Private ticket)

All help is appreciated, this is a very annoying problem!

[Hadi Deknache]

Hi Vidar,

After checking the makefile, it seems to be the case. The build_rules are compiled with other preprocessor flags and therefore result in enabling the log, causing the application to fail. Thanks for your time and help!