https://devzone.nordicsemi.com/f/nordic-q-a/111257/zephyr-3-4-99-main-function-conflicts-with-one-in-mcubootHello, I &#39;m updating from Zephyr 3 .2.99 to Zephyr 3 . 4.99 . I attempted to add a main() function to my application . (Heretofore I have not been using a main() function , just spawning threads . ) I &#39;m using MCUboot . I got this build failureen-USTelligent Community 13Tue, 21 May 2024 13:32:28 GMThttps://devzone.nordicsemi.com/thread/485145?ContentTypeID=1Tue, 21 May 2024 13:32:28 GMT137ad170-7792-4731-bb38-c0d22fbe4515:555d6b09-a8a0-4eb5-a98a-88a463879c13Vidar Berg<p>Hello,</p> <p>Did you include MCUBoot as a child image (see&nbsp;<a href="https://developer.nordicsemi.com/nRF_Connect_SDK/doc/2.6.1/nrf/config_and_build/multi_image.html#multi-image-builds">Multi-image builds</a>) in your project by adding&nbsp;CONFIG_BOOTLOADER_MCUBOOT=y prj.conf, or did you do in some other way? I don&#39;t see how or why the mcuboot project would build with source files from your &quot;common&quot; directory, that is not something I have encountered before.</p> <p>Thanks,</p> <p>Vidar</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/484764?ContentTypeID=1Thu, 16 May 2024 16:52:37 GMT137ad170-7792-4731-bb38-c0d22fbe4515:b10fbb9a-ed6c-47d1-b18a-f7bbf3fb8565Yaron Shragai<p>Turns out that the issue is that I placed that <span style="font-family:&#39;courier new&#39;, courier;">main()</span> function in a file in the <span style="font-family:&#39;courier new&#39;, courier;">common</span> dir of my project.</p> <p>Looks like MCUboot includes the <span style="font-family:&#39;courier new&#39;, courier;">common</span> dir of my project.</p> <p>Is there something magickal about any dir, anywhere, whose name is &quot;<span style="font-family:&#39;courier new&#39;, courier;">common</span>&quot;? Does MCUboot automatically include those?</p> <p>What are other magickal aspects of the MCUboot build that I should be aware of?</p> <p>Thanks!</p><div style="clear:both;"></div>