Keil Logo

Arm functional safety C library

Learning Platform

Arm provides a special C library targeting functional safety applications.The library implements a restricted subset of functions specified in the ISO C99 C language standard and comes with usage guidelines and examples on how to work effectively with it.


Arm runtime C libraries

The runtime Arm C library consists of all functions that are defined by the ISO C99 library standard. It allows users to redefine these functions in own application. And it also contains functions that are called implicitly by the Arm Compiler and Arm extensions, that are not defined by the ISO C library standard, but are included in the library.

Arm functional safety C library

The FuSa C Library provides a limited subset of the C library suitable for developing safety-critical embedded applications on Arm architecture compliant devices.

Specifically, it provides the following:

  • A subset of the functions defined in the ISO C Language Specification.
  • The Run-time Application Binary Interface (ABI) for the Arm Architecture.
  • Utility support functions.

FuSa RTS documentation provides vital usage instructions along with important information about the behavior of the FuSa C Library.

  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.