Mixed-Language Toolchains for Automotive Embedded Software

Automotive software platforms are evolving toward larger, software-driven architectures that require secure and maintainable code across multiple system components. In this context, HighTec EDV-Systeme has expanded its LLVM-based Rust and C/C++ compiler toolchain to support Renesas RH850/U2x microcontrollers.

Expanding development options for automotive microcontrollers
The Renesas RH850/U2x series is a family of high-performance 32-bit automotive microcontrollers designed for applications such as zone and domain controllers, powertrain management, and chassis control systems. These MCUs combine multi-core processing capabilities with functional safety mechanisms supporting system designs up to ASIL D.

HighTec’s compiler toolchain allows developers working with this microcontroller family to integrate memory-safe Rust code alongside existing C or C++ software. The mixed-language approach enables development teams to introduce modern programming techniques without replacing established codebases used in automotive electronic control units.

The toolchain utilizes architectural features of the Renesas platform to generate deterministic code execution, which is essential for resource-constrained and safety-critical embedded systems.

LLVM-based toolchain with functional safety qualification
HighTec’s compiler tools are built on the LLVM open-source compiler infrastructure, which provides optimization capabilities and access to a broad development ecosystem. The tool suite has been qualified for automotive applications according to ISO 26262 ASIL D for functional safety and ISO 21434 for automotive cybersecurity.

The platform also includes a dedicated Qualification Kit intended to simplify the certification process for automotive software projects. Combined with HighTec’s long-term device support strategy, the approach supports the extended development and maintenance cycles common in the automotive software lifecycle.

Introducing Rust into established automotive software stacks
Rust is increasingly considered for safety-critical software because of its built-in mechanisms for memory safety and concurrency control. HighTec’s hybrid toolchain enables developers to integrate Rust components into existing C/C++ architectures without abandoning legacy code.

This approach allows development teams to reuse proven low-level C software components while introducing new modules written in Rust. It provides a gradual migration path toward mixed-language ECU software architectures used in software-defined vehicles (SDV).

The approach also supports AUTOSAR-based software environments. Developers can maintain existing AUTOSAR infrastructures while implementing new application components in Rust. Proven low-level components such as MCAL layers, as well as Basic Software (BSW) and Runtime Environment (RTE) modules from suppliers such as Vector Informatik, can continue to be reused.

Integration within the Renesas development ecosystem
Support for the RH850/U2x microcontroller series expands HighTec’s role within the Renesas development ecosystem. The Rust and C/C++ compiler toolchain integrates with the Renesas development environment and supports CI/CD-based embedded development workflows.

At the same time, Renesas provides MCAL implementations compatible with HighTec’s RH850 compiler, enabling developers to build software stacks that combine hardware abstraction layers with mixed-language application code.

HighTec plans to extend compiler support to additional Renesas microcontroller families as part of its broader multi-architecture strategy.

Demonstration at embedded world 2026
HighTec presented this mixed-language development approach at embedded world 2026, held 10–12 March 2026 in Nuremberg, Germany. At booth 4-432 in hall 4, the company demonstrated interoperability between C and Rust within a single embedded project running on a Renesas RH850/U2x microcontroller.

The demonstration combined low-level drivers written in C with a Rust-based application layer, illustrating how mixed-language development workflows can be applied to safety-critical automotive software systems.

www.hightec-rt.com

Edited by industrial journalist, Aishwarya Mambet — AI-powered.