https://devzone.nordicsemi.com/f/nordic-q-a/9337/gcc-can-compile-with-object-file-compiled-from-keil-arm-complierHi, I&#39;m converting my project to OSX GNU from windows keil because of license problem. There is some .o files made by keil-arm complier in my previous project. and I don&#39;t have those c files. and I tried compile projects and when it try to linken-USTelligent Community 13Mon, 21 Sep 2015 07:38:34 GMThttps://devzone.nordicsemi.com/thread/34477?ContentTypeID=1Mon, 21 Sep 2015 07:38:34 GMT137ad170-7792-4731-bb38-c0d22fbe4515:872792ac-c9c9-450a-b98e-b737a89d8fc5benevbright<p>Thank RK. I will have to get those c files.</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/34476?ContentTypeID=1Sun, 20 Sep 2015 23:48:04 GMT137ad170-7792-4731-bb38-c0d22fbe4515:9b20b848-f27b-445c-b846-32ee3861bfd3RK<p>No you can&#39;t link random files together unless they are in compatible recognized formats, which these aren&#39;t.</p> <p>But of course you have the original .c files, keil didn&#39;t&#39; magically produce .o files fro thin air, you just need to find them and add them to your project.</p><div style="clear:both;"></div>