Re: [PATCH] libstdc++: arm: convert vpadd_* operands to intrinsic types [PR122981]

Hi Matthias,

On 2026-08-14 17:37, Matthias Kretz wrote:
> Thanks Torbjorn,
> 
> I've been trying really hard to reproduce the issue. And failed so far.
> I now tried to build a --target=arm-none-eabi GCC locally, but that doesn't
> compile. How do you compile it?

I'm using this way to build an arm-none-eabi toolchain:
https://github.com/STMicroelectronics/gnu-tools-for-stm32/

To launch the build, simply run (assuming that you are only interested in a toolchain for the build host)

./build-prerequisites.sh --skip_steps=mingw && ./build-toolchain.sh --skip_steps=mingw

It will take a while, but you will eventually have an arm-none-eabi toolchain in ./install-native.

To build any GCC revision, simply replace src/gcc with a checkout of the GCC sources you want to build.

An alternative approach is to follow what Arm is pointing to by using https://gitlab.arm.com/tooling/gnu-devtools-for-arm, but I've not tried this myself.

> I fear we're currently at a point where neither of us really understand the
> problem and whether your patch is the best solution.

I see that most of the commits for the experimental/bits/simd* where done by you over the years, so if you do not know how this works, then who might?

Kind regards,
Torbjörn