Starting with Rust 1.97, the nvptx64-nvidia-cuda compilation target for NVIDIA GPUs will enforce higher baseline requirements for both the PTX ISA version and the GPU architecture. This means that older GPUs and CUDA drivers will no longer be supported. This Q&A explains what changes, why they are happening, and how to update your configuration.
What exactly is the nvptx64-nvidia-cuda target and how does it work?
The nvptx64-nvidia-cuda target is used to compile Rust code for NVIDIA GPUs. The compiler outputs PTX (Parallel Thread Execution) intermediate code. Two version choices control the output:
- GPU architecture (e.g.,
sm_70,sm_80) – determines which GPU models can run the PTX. - PTX ISA version – determines which CUDA driver versions can load and JIT-compile the PTX.
By adjusting these parameters, developers can target a wide range of hardware, but the defaults and minimums are what Rust 1.97 will change.
What specific changes will Rust 1.97 introduce?
In Rust 1.97, the minimum supported PTX ISA version rises to 7.0 (requires CUDA 11 driver or newer), and the minimum GPU architecture rises to SM 7.0 (compute capability 7.0 or greater). This means the compiler will no longer produce PTX that can run on pre-Volta GPUs (like Maxwell or Pascal) or work with CUDA 10-era drivers. The default -C target-cpu will also become sm_70 if you don't specify one.
Why is the Rust team raising these baseline requirements?
Previously, Rust attempted to support a very broad range of architectures, but in practice this led to numerous defects, including compiler crashes and miscompilations. By dropping support for older hardware (the most recent affected GPUs date back to 2017 and are no longer actively supported by NVIDIA), the Rust team can focus on ensuring correctness and performance for the remaining supported hardware. The maintenance effort for those older architectures was substantial, so this change enables more efficient development.
If I have an older GPU or CUDA driver, what happens after upgrading?
If you’re using a CUDA driver that does not support PTX ISA 7.0 (CUDA 10 or older), Rust 1.97 will no longer generate PTX compatible with that driver. Similarly, if your GPU has compute capability below 7.0 (e.g., Maxwell or Pascal), you will no longer be able to produce compatible PTX. You will need to either keep using an older Rust version for such environments or update your hardware/drivers to meet the new minimums.
How should I update my Rust build configuration for 1.97?
Assuming you have a CUDA 11+ driver and a compute capability 7.0+ GPU:
- If you do not specify
-C target-cpu, the new default will besm_70. Your build should continue to work but will lose compatibility with older GPUs. - If you currently specify an older architecture (e.g.,
sm_60), you must either remove that flag (to let it default tosm_70) or update it tosm_70or newer. - If you already use
sm_70or newer, no change is needed.
For more details, consult the platform support documentation.
What are the long‑term benefits of this baseline increase?
By cutting off older, less‑used hardware, the Rust compiler can be streamlined and tested more thoroughly on modern GPUs. This reduces compiler bugs, improves reliability, and allows the team to concentrate on performance optimizations for Volta, Turing, Ampere, and later architectures. The change also aligns with NVIDIA’s own support timeline, making the Rust ecosystem more predictable for developers targeting current hardware.