Old SDK12.1 based bootloader not working when compiled with arm gcc 9.2.1https://devzone.nordicsemi.com/f/nordic-q-a/62264/old-sdk12-1-based-bootloader-not-working-when-compiled-with-arm-gcc-9-2-1I have a project that I&#39;ve joined recently that is based on SDK12.1. The bootloader does not seem to work when compiled with a currently arm-gcc version (9.2.1). It does work when compiled with 4.9.3. By &quot;not work&quot; I mean the bootloader gets stuck, willen-USTelligent Community 13Mon, 08 Jun 2020 09:26:25 GMTRE: Old SDK12.1 based bootloader not working when compiled with arm gcc 9.2.1https://devzone.nordicsemi.com/thread/253726?ContentTypeID=1Mon, 08 Jun 2020 09:26:25 GMT137ad170-7792-4731-bb38-c0d22fbe4515:b7754bd1-2223-48af-b20a-a5de7e6d03d7Vidar Berg<p>Hello,</p> <p>Please try disabling the link-time optimization (i.e., remove &#39;-flto&#39; option from Makefile) and see if it gives the same result. We have had some problems with this optimization and certain releases of GCC. As stated in the release notes, SDK v12. was tested and verified with the 4.9 2015q3 release.</p><div style="clear:both;"></div>