https://devzone.nordicsemi.com/f/nordic-q-a/46089/gcc-version---4-9-2015q3-with-sdk-v15-2-v15-3Hi I want to use GCC 4.9 2015q3 to build code on SDK v15.2 and v15.3 but it shows it cannot find 6 2017-q2-update and 7 2018-q2-update. Checked Infocenter - Secure DFU on SDK v15.2, it shows need to use 4.9 2015q3 to build micro-ecc but it buildsen-USTelligent Community 13Fri, 12 Apr 2019 06:16:14 GMThttps://devzone.nordicsemi.com/thread/181750?ContentTypeID=1Fri, 12 Apr 2019 06:16:14 GMT137ad170-7792-4731-bb38-c0d22fbe4515:9311143a-63fb-49cb-ae6c-869e6932661eEinar Thorsrud<p>Hi Atlas,</p> <p>As <a href="https://devzone.nordicsemi.com/members/mojo">Mojo</a> wrote, you need to set the correct version and path in &lt;SDK&gt;\components\toolchain\gcc\Makefile.windows (or&nbsp;Makefile.posix if you are on Mac or Linux). But please note that SDK 15.2 has been tested with&nbsp;GCC ARM Embedded 6.3 2017-q2-update and SDK 15.3 has been tested with GCC ARM Embedded 7.2018q2.update. We recommend you stick with the tested version.</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/181681?ContentTypeID=1Thu, 11 Apr 2019 15:13:48 GMT137ad170-7792-4731-bb38-c0d22fbe4515:a5f811b6-5229-4e24-a835-2935e26f5ecbMojo<p>check your makefile to set the correct path for the compiler. &nbsp;You can use the latest gcc too. &nbsp;Doesn&#39;t have to be version 4.9.&nbsp;</p><div style="clear:both;"></div>