As announced in previous posts, we’re introducing many changes ahead of the Mbed OS 6 release to improve the quality of the code and user experience. A major focus is making the code base more maintainable and easier to use. We started by removing a large number of deprecated APIs. With this work almost complete,  we’re now removing references of unsupported or deprecated tools.

We no longer support ARM Compiler 5; it was superseded in Mbed OS by ARM Compiler 6, which offers the most advanced C and C++ compilation toolchain for Arm Cortex® processors. Arm Compiler 6 provides better performance for a wide range of embedded applications, efficient code generation and better diagnostics. Of particular interest, it brings the advantages of link-time code optimization (LTO), which removes unused and redundant code.

We are therefore disabling ARM Compiler 5 in our tools and removing specific references to it from the source files, except for code imported from external libraries. This removes unused code from our code base.

We are also removing the uARM toolchain, which is the ARMC6 toolchain with the micro C library. Users working with our Bare Metal profile can now use a target configuration parameter to build with micro C and newlib-nano, removing the need to invoke the uARM toolchain. 

We continue to support our customers and the developer community in the best possible way by improving our code quality and making our code easier to use.