# Explore Arm Memory Tagging Extension with an example C program

## In this learning path

- [Introduction](https://learn.arm.com/learning-paths/mobile-graphics-and-gaming/mte/)
- [Create and compile an example C application to explore Arm MTE](https://learn.arm.com/learning-paths/mobile-graphics-and-gaming/mte/mte/)
- [Run the example application to explore Arm MTE](https://learn.arm.com/learning-paths/mobile-graphics-and-gaming/mte/run-mte-example/)
- [Next Steps](https://learn.arm.com/learning-paths/mobile-graphics-and-gaming/mte/_next-steps/)

## About this Learning Path

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| Skill level: | Introductory |
| Reading time: | 20 min |
| Last updated: | 19 Aug 2026 |

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| Author: | Jason Andrews , Arm<br>[GitHub](https://github.com/jasonrandrews)<br>[LinkedIn](https://linkedin.com/in/jason-andrews-7b05a8) |
| Arm IP: | [Cortex-A](https://support.arm.com/?tab=compute-ip&Product%20Type=Application%20Processors) |
| Tags: | [Performance and Architecture](https://learn.arm.com/tag/performance-and-architecture) [Linux](https://learn.arm.com/tag/linux) [QEMU](https://learn.arm.com/tag/qemu) |

### Who is this for?
This is an introductory topic for developers who want to gain experience with the Arm Memory Tagging Extension (MTE).

### What will you learn?
After completing this Learning Path, you'll be able to perform the following tasks:
- Build an MTE-enabled C program on AArch64 Linux
- Run the program to observe MTE detecting an invalid memory access
- Use QEMU to run the example when MTE hardware is unavailable

### Prerequisites
Before starting, you'll need the following prerequisites:
- An AArch64 Linux development machine. You can also use a cloud instance. For more information, see the list of [Arm cloud service providers](https://learn.arm.com/learning-paths/servers-and-cloud-computing/csp/).

### Summary
You’ll explore Arm MTE on an `aarch64` Linux system. First, you’ll build and run a small C program that triggers buffer-overflow and use-after-free errors, then observe the resulting faults or diagnostics. You’ll use a recent Arm system or supported Arm-based cloud instance to relate MTE behavior to invalid memory accesses.

### Frequently asked questions

**How do I know if my system can demonstrate MTE?**

MTE is implemented in Armv8.5-A and Armv9-A processors. Verify that you’re using an AArch64 Linux system with hardware that supports MTE. Otherwise, the example might not show tagging-related behavior.

**What result should I expect when running the example program?**

Expect behavior that illustrates MTE catching memory safety issues, such as a fault or diagnostic triggered by an invalid access. The outcome should align with the bug the program intentionally exercises.

**Can I run the example without MTE hardware?**

Yes. Install `qemu-user` and run the example with `qemu-aarch64 ./mte-example`. This lets you exercise MTE behavior when the processor doesn’t implement MTE.

**What should I check if the program runs without showing any MTE effects?**

Confirm you’re on AArch64 Linux and that the processor implements MTE (Armv8.5-A or Armv9-A). If the processor lacks MTE support, install `qemu-user` and run `qemu-aarch64 ./mte-example` to exercise the MTE behavior through emulation.

**What invalid memory access does the example demonstrate?**

The example writes beyond a 16-byte allocation granule at offset `0x10`. MTE detects the tag mismatch and should generate an exception.