docs: describe the Linux-only host

README and AGENTS.md stop documenting build.cmd, LIBCXX_DIR, the
DLL-plus-launcher design rule and the cmd-over-SSH gotcha. The runner
section also drops Ssh, SshWin and Wsl, which were removed from the
code earlier but still had README entries, and the stale pointer to a
deleted cross-arch test. ci.yaml loses the commented-out Windows build,
staging and upload steps and the comments that counted them.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
This commit is contained in:
Jorijn van der Graaf 2026-10-02 21:56:38 +02:00
commit 68e9b6bfa5
Signed by: jorijnvdgraaf
GPG key ID: 2937E59CDCC1BCFB
3 changed files with 16 additions and 58 deletions

View file

@ -154,18 +154,15 @@ Outcomes: ✅ pass, ❌ fail, 💥 crash (with signal name), ⏱ timeout, ⏭ sk
```cpp
TestRunner::Local() // run on this machine (default)
TestRunner::Cmd("wine") // local exec via prefix command
TestRunner::Ssh("hostname") // remote linux via scp + ssh
TestRunner::SshWin("winhost") // remote windows via scp + ssh-cmd.exe
TestRunner::Wsl() // Linux binaries via WSL2 (Windows host)
```
`Cmd(cmd)` is a generic `<cmd> <bin> <args>` prefix runner — covers wine, qemu-user, valgrind, gdbserver, anything with that shape. Probes via `which <cmd>` (or `where` on Windows hosts). The `Ssh` variants `scp -r` the test's whole bin dir, run the binary remotely, then clean up; each invocation uses a unique remote subdir so parallel runs don't collide. `Wsl()` mirrors the SSH model but copies the bundle into WSL's native filesystem (faster than executing in-place from `/mnt/c`) — useful when a Windows host wants to exercise Linux test binaries.
`Cmd(cmd)` is a generic `<cmd> <bin> <args>` prefix runner — covers wine, qemu-user, valgrind, gdbserver, anything with that shape. Probes via `which <cmd>`.
For elaborate setups (rsync, ssh ControlMaster, env vars on the spawn, `QEMU_LD_PREFIX` for sysroots), construct `TestRunner` directly — `copy`/`exec`/`cleanup`/`probe` are public string fields with `{bundle}`, `{remote_bundle}`, `{bin}`, `{bin_name}`, `{args}` placeholders.
For cross-arch builds, set `cfg.sysroot` on the `Configuration` to point at a sysroot for the target. `BuildStdPcm` and the compile/link commands both consume it: `--sysroot=<path>` is passed to clang, and `<sysroot>/usr/share/libc++/v1/std.cppm` is precompiled instead of the host's. The cheapest aarch64 sysroot is an extracted [Arch Linux ARM rootfs](http://os.archlinuxarm.org/) plus `libc++` + `libc++abi` + `gcc` installed into it via `pacman --root <rootfs> --config <alarm-pacman.conf> --dbpath <rootfs>/var/lib/pacman -Sy …` (point pacman at ALARM's mirrors via explicit config to avoid pulling host-arch packages). See `tests/CrossArchAarch64/inner/` for a working sysroot+qemu example.
For cross-arch builds, set `cfg.sysroot` on the `Configuration` to point at a sysroot for the target. `BuildStdPcm` and the compile/link commands both consume it: `--sysroot=<path>` is passed to clang, and `<sysroot>/usr/share/libc++/v1/std.cppm` is precompiled instead of the host's. The cheapest aarch64 sysroot is an extracted [Arch Linux ARM rootfs](http://os.archlinuxarm.org/) plus `libc++` + `libc++abi` + `gcc` installed into it via `pacman --root <rootfs> --config <alarm-pacman.conf> --dbpath <rootfs>/var/lib/pacman -Sy …` (point pacman at ALARM's mirrors via explicit config to avoid pulling host-arch packages).
For `--target=x86_64-w64-mingw32` (Windows from Linux), V2's pipeline cross-compiles as long as `mingw-w64` is installed. Pair it with `--runner=cmd:wine` (no VM needed) or `--runner=sshwin:winhost` (real Windows). Full MSVC ABI (`x86_64-pc-windows-msvc`) cross-compile from Linux is not yet wired; use MinGW for now. `-fuse-ld=lld` is auto-injected on every link, and `-lstdc++exp` is auto-linked for the mingw target so user projects don't need to declare those flags.
For `--target=x86_64-w64-mingw32` (Windows from Linux), the pipeline cross-compiles as long as `mingw-w64` is installed. Pair it with `--runner=cmd:wine` to run the result. Only the MinGW ABI is supported; there is no MSVC target and no Windows host. `-fuse-ld=lld` is auto-injected on every link, and `-lstdc++exp` is auto-linked for the mingw target so user projects don't need to declare those flags.
### Configuring runners
@ -192,12 +189,9 @@ Spec grammar:
```
local
cmd:<command> # cmd:wine, cmd:qemu-aarch64, cmd:valgrind, ...
ssh:<host>[:<remoteDir>]
sshwin:<host>[:<remoteDir>] # cmd.exe-shell variant for Windows remotes
wsl[:<remoteDir>] # Windows host -> Linux binaries via WSL2
```
Each runner carries a `probe` command (e.g. `which wine`, `ssh -BatchMode=yes <host> true`); if it fails, every test using that runner is reported as ⏭ skipped and the rest of the suite continues. Skipped tests count toward the summary but don't fail the suite (`AllPassed()` returns true on skip-only runs).
Each runner carries a `probe` command (e.g. `which wine`); if it fails, every test using that runner is reported as ⏭ skipped and the rest of the suite continues. Skipped tests count toward the summary but don't fail the suite (`AllPassed()` returns true on skip-only runs).
### Linking the parent project's library