`mask_sdf` SIGSEGVd after printing `test result: ok`, and the workaround
was to hand the device to the process with `mem::forget` on the reading
that "dropping a wgpu device on Venus segfaults". Every part of that
except the symptom was wrong.
`rigs/gpu-probe`'s new `teardown` bin is the experiment, one variable per
mode: the same open-and-close exits 0 on the main thread and SIGSEGVs on
a spawned one; it needs no GPU work and no device, only an instance; raw
`ash` does it with no wgpu involved at all; and keeping the instance
alive fixes it. Destroying the last VkInstance makes the loader dlclose
the ICD, and Mesa's ICD here registers a pthread_key_create destructor
into its own text without `-z nodelete`, so glibc calls it through
unmapped memory when the thread exits. libtest runs every #[test] on a
spawned thread, which is the whole reason this looked like a drop bug.
`VK_LOADER_DISABLE_DYNAMIC_LIBRARY_UNLOADING=1` confirms the mechanism.
So the fix is one `wgpu::Instance` for the process -- what wgpu asks for
anyway -- and the device, queue and everything else drop normally again.
The escape and its paragraph of reasons are gone.
Also: the machine-level graphics notes duplicated in docs/RUST.md,
run-headless.sh and two source comments now point at the
`this-machine-graphics` skill, which is the only copy.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Layer 2 of docs/RUST.md's "Three test layers":
./run-headless.sh phone --phone --shot /tmp/p.png -- -p transcript-fixture
opens `transcript-fixture`'s screen -- the same fixture and the same
fold the headless tests and the Android bench use -- in a window at the
phone's own 1080x2424 and `content_scale` 2.55, and screenshots it. 15
seconds, warm. `--replay FILE` drives one of the `.touch` recordings
into it and writes `<shot>-before.png` too, so "the list moved" is two
pictures: the flick carries it back about seven turns of the fixture.
Two things this needed.
**The desktop backend now lays out in physical pixels with a density,
exactly as Android does** (`default::content_scale`, overridable with
`IRIS_SCALE`, which is how `--phone` hands it the phone's). It used to
divide winit's coordinates into a separate "logical" space, which left
`UiRenderState::resize` (physical, from `WindowEvent::Resized`) and the
window uniform (logical) disagreeing on any display whose scale factor
is not 1.0, and rasterised glyphs at one resolution to show them at
another. At 1.0 -- every display here -- the numbers are unchanged, and
the `tabs` screenshot is identical.
**`rig-input`'s `replay-touch`** puts a gesture on screen. This
machine's compositor has no pointer to move: sway runs on the headless
backend with no input devices, so `swaymsg seat - cursor press` reports
success and `swaymsg -t get_seats` shows `capabilities: 0`. wlroots 0.19
dropped `WLR_HEADLESS_INPUTS` and ydotool's uinput device would be
ignored by a compositor not reading libinput, so the virtual-pointer
protocol is what is left. It parses the *same* `TouchScript` the
harness does, so one recording drives both layers.
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
desktop-app (RUST.md's E4) is a real crate binary a person runs, not a
demo under examples/, and it needs its own argv (--ca, --link) to start
at all -- neither of which the script had a way to express. --bin swaps
`cargo build --example`/`target/debug/examples/NAME` for the `--bin`
equivalents; $RUN_HEADLESS_ARGS is word-split into the launched binary's
own argv, since no example ever needed one before.
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
This VM has no display but does have a real GPU -- Vulkan 1.4 through
Venus and GL 4.6 through virgl, onto the host's card -- so the only thing
missing for a winit window is a compositor. Same trick `emu` uses for the
Android emulator: a headless sway, with grim for the picture.
It starts its own compositor rather than joining `emu`'s. sway tiles, so
adding a window to the one an emulator sits in resizes that emulator, and
a peer session's `emu up` could join at any moment. Xwayland is off here
because winit speaks Wayland; `emu` forces it on only because the Android
emulator's renderer speaks GLX.
It waits for the window to be mapped rather than sleeping a fixed time:
the first version's fixed sleep captured an all-black screen when sway
had started in the same invocation, which is indistinguishable from an
app that draws nothing.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
irisandClaude Opus 5