按推荐建议，继续执行

结论：新增 compatibility-validation 与 drift-report，记录当前 native 验证链路、fixture 覆盖、无漂移规则和已知缺口，继续约束移植行为跟随 LinuxCNC 源程序。

wasm-port/docs/compatibility-validation.md

@@ -0,0 +1,95 @@
+# Compatibility Validation
+
+## Purpose
+
+This document records how the standalone LinuxCNC WASM port currently proves
+that migrated behavior remains tied to LinuxCNC source code and fixture
+semantics.
+
+The primary validation command is:
+
+```bash
+wasm-port/tests/native/verify_native_probes.sh
+```
+
+## Validation Chain
+
+The native validation script runs these checks in order:
+
+1. `tools/verify_upstream_baseline.sh`
+   Confirms `../linuxcnc` is at the recorded upstream commit in
+   `tools/upstream-baseline.txt`.
+2. `tools/verify_vendor_sync.sh`
+   Confirms every manifest file is present in `vendor/linuxcnc/`, no extra
+   vendored file exists, and every vendored file is byte-identical to upstream.
+3. `tools/verify_no_standalone_cnc_semantics.sh`
+   Confirms standalone code has not reintroduced `Interp::convert_g()`.
+4. `tools/build_native_probes.sh`
+   Builds native source probes and standalone harnesses from vendored
+   LinuxCNC source plus narrow runtime wrappers.
+5. `tests/native/verify_native_probes.sh`
+   Checks probe exit codes, source-probe coverage, harness stdout, canonical
+   fixture events, and expected error behavior.
+
+## Source Coverage
+
+Every `.c` and `.cc` entry in `tools/source-manifest.txt` must have a
+corresponding `*_source_probe` entry in `build/native/source-probes.tsv`.
+The validation fails if:
+
+- a manifest source file lacks a source probe;
+- a source probe references a file not listed in the manifest;
+- a manifest file is duplicated;
+- vendored files drift byte-for-byte from upstream LinuxCNC.
+
+## Current Native Harnesses
+
+| Harness | Purpose |
+| --- | --- |
+| `linuxcnc_ini_probe` | Validates vendored LinuxCNC INI parsing can be used standalone. |
+| `linuxcnc_interp_state_probe` | Validates interpreter state constants and structs compile under the standalone boundary. |
+| `linuxcnc_namedparam_harness` | Validates LinuxCNC named parameter behavior, `_ini[...]`, and `_hal[...]` adapter resolution. |
+| `linuxcnc_interp_minimal_harness` | Runs G-code fixtures through vendored LinuxCNC parser/execution/conversion code and captures canonical events. |
+| `linuxcnc_parameter_file_harness` | Validates LinuxCNC parameter file restore/save behavior and required/read-only parameter handling. |
+| `linuxcnc_tp_api_probe` | Validates vendored LinuxCNC trajectory planner calls for linear, arc, and queued motion paths. |
+
+## Fixture Coverage
+
+Positive G-code fixtures currently cover:
+
+- linear traverse/feed
+- arc semantics
+- modal absolute/incremental motion
+- position parameters
+- canned cycles
+- coordinate offsets
+- feed and motion control modes
+- probing
+- threading and rigid tap
+- NURBS G5/G6
+- spindle orient
+- tool semantics
+- tool table setup
+- named and numbered parameters
+- O-word subroutines
+- program-end modal reset
+- canonical runtime edge calls
+
+Negative fixtures currently cover:
+
+- zero-feed `G1`
+- arc radius mismatch
+- zero-radius arc
+- read-only named parameter writes
+- read-only numbered parameter writes
+- missing tool
+- missing tool length offset
+
+## Validation Boundaries
+
+Current validation is native-only. WASM, browser, SDK, OPFS, and full
+machine-session validation remain future work.
+
+The current fixture expectations validate standalone behavior against the
+vendored LinuxCNC source path. They do not yet run a side-by-side native
+LinuxCNC executable comparison for each fixture.

wasm-port/docs/drift-report.md

@@ -0,0 +1,60 @@
+# Drift Report
+
+## Current Status
+
+As of the current upstream baseline, no byte-level drift is allowed between
+files listed in `tools/source-manifest.txt` and the matching files under
+`../linuxcnc/`.
+
+The enforced upstream baseline is:
+
+```text
+60597ee0718873d2449058c824262a275e5e4bad
+```
+
+`tools/verify_vendor_sync.sh` enforces this by comparing every manifest file
+against upstream during native validation.
+
+## Allowed Standalone Boundaries
+
+The following differences are intentional runtime boundaries, not LinuxCNC
+semantic rewrites:
+
+| Boundary | Standalone treatment |
+| --- | --- |
+| RTAPI | Minimal compatibility shim in `runtime/core/shims/rtapi.h`. |
+| HAL lookup | Standalone HAL adapter for `_hal[...]` named parameter reads. |
+| INI lookup | Standalone INI adapter around vendored LinuxCNC INI parser behavior. |
+| Canonical output | Canonical calls are captured as test events instead of driving hardware. |
+| Python/remap | Python/remap hooks are stubbed at the runtime edge. |
+| Dynamic interpreter path | `interp_base.cc` probe uses standalone `EMC2_HOME` compile-time path boundary. |
+| Realtime scheduler | TP probes seed deterministic status/config data instead of running LinuxCNC realtime process topology. |
+| Browser storage | OPFS remains outside the native core and is not yet connected. |
+
+## Enforced Non-Drift Rules
+
+- Do not edit `../linuxcnc/`.
+- Do not patch vendored files without adding a patch under `patches/` and
+  documenting the reason.
+- Do not add standalone `Interp::convert_g()`.
+- Do not add `.c` or `.cc` manifest files without a source compile probe.
+- Do not sync from a different upstream commit without updating
+  `tools/upstream-baseline.txt` and `docs/scope-and-baseline.md`.
+
+## Known Gaps
+
+- No browser/WASM parity tests yet.
+- No JS SDK validation yet.
+- No OPFS persistence validation yet.
+- Full kinematics implementation files are not yet extracted.
+- Full 3-axis, non-trivial kinematics, and 5-axis machine baselines are not
+  established.
+- Fixture expectations are currently checked against the standalone vendored
+  source path, not by running a native LinuxCNC binary for every fixture.
+
+## Current Drift Conclusion
+
+Within the native extracted-core scope, the port currently has no permitted
+byte-level drift from vendored LinuxCNC source files. All current behavior
+coverage is guarded by upstream baseline validation, vendor sync validation,
+source compile probes, native harnesses, and fixture checks.

wasm-port/docs/porting-steps-standalone.md

@@ -500,6 +500,11 @@ Current verified progress:
 - `docs/source-reuse-map.md` records the current vendored LinuxCNC source
   reuse matrix and dependency matrix, tying each extracted group to its
   standalone runtime boundary and validation path.
+- `docs/compatibility-validation.md` records the current validation chain,
+  source coverage requirements, native harnesses, fixture coverage, and
+  validation boundaries.
+- `docs/drift-report.md` records current no-drift enforcement, allowed
+  standalone runtime boundaries, known gaps, and the current drift conclusion.
 
 ## Phase 4: Port INI Parsing Without Editing Upstream