Re: [meson.bbclass] bindgen_clang_arguments lacks C++ include paths, breaks C++ bindgen (mesa rusticl)

[Royyan Zahir <royzah@gmail.com>]

On Mon, 21 Sep 2026, Paul Barker wrote:
> Yes, I'd like you to confirm that the error happens on stock
> poky/qemuarm64 with just the DISTRO_FEATURES change to enable opencl.
>
> Also, please quote the email you're replying to so it's easier to follow
> the conversation.

Sorry about the quoting, fixed here.

Ran it, and it does NOT reproduce on stock poky. So my report was wrong, sorry for the noise.

oe-core f7397af248 + bitbake 2.18 0ad6c1c34, nothing else, local.conf was just:

  MACHINE = "qemuarm64"
  DISTRO_FEATURES:append = " opencl"

bitbake mesa: 2659 tasks, all succeeded.

rusticl was definitely on and bindgen definitely ran, so it is not that the path was skipped:

  gallium-rusticl=true                                    (log.do_configure)
  bindgen appears 4x in log.do_compile
  build/src/gallium/frontends/rusticl/rusticl_llvm_bindings.rs   13502 bytes, generated fine

And the interesting bit: bindgen_clang_arguments in that build has no C++ include paths either, same as ours:

  bindgen_clang_arguments = ['-mcpu=cortex-a57+crc', '-mbranch-protection=standard',
    '-fstack-protector-strong', '-O2', '-D_FORTIFY_SOURCE=2', '-Wformat',
    '-Wformat-security', '-Werror=format-security',
    '--sysroot=.../mesa/26.0.5/recipe-sysroot', '--target=aarch64-oe-linux']

so clang finds cassert anyway. My "any recipe doing C++ bindgen will hit this" claim is just wrong, ignore it.

One difference I can see: stock poky pulls LLVM 22.1.8, our stack is on 22.1.3 (meta-qcom pins it). The failure is clang chasing cassert from llvm/ADT/DenseMapInfo.h, so an older LLVM header pulling in something slightly different is my current guess. Guess only, I have not tested it yet.

Next thing I can do is the same stock build plus meta-qcom and its LLVM pin, one variable at a time, and see which one flips it. Will report back if you think it is worth it, otherwise happy to just carry our bbappend and drop this.

Royyan