Keil Logo

Creating a symdefs file

6.5.1 Creating a symdefs file

You can specify a symdefs file on the linker command-line.

You can use a symdefs file, for example, if you have one image that always resides in ROM and multiple images that are loaded into RAM. The images loaded into RAM can access global functions and data from the image located in ROM.
Use the armlink option --symdefs=filename to generate a symdefs file.
The linker produces a symdefs file during a successful final link stage. It is not produced for partial linking or for unsuccessful final linking.


If filename does not exist, the linker creates the file and adds entries for all the global symbols to that file. If filename exists, the linker uses the existing contents of filename to select the symbols that are output when it rewrites the file. This means that only the existing symbols in the filename are updated, and no new symbols (if any) are added at all. If you do not want this behavior, ensure that any existing symdefs file is deleted before the link step.
Non-ConfidentialPDF file icon PDF versionARM DUI0377H
Copyright © 2007, 2008, 2011, 2012, 2014-2016 ARM. All rights reserved. 
  Arm logo
Important information

This site uses cookies to store information on your computer. By continuing to use our site, you consent to our cookies.

Change Settings

Privacy Policy Update

Arm’s Privacy Policy has been updated. By continuing to use our site, you consent to Arm’s Privacy Policy. Please review our Privacy Policy to learn more about our collection, use and transfers
of your data.