按推荐建议，继续执行

结论：已接入 LinuxCNC NURBS G6 canonical 边界事件记录，并新增 G6.2 回归 fixture；原生 probe 验证通过。

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

@@ -409,6 +409,12 @@ Current verified progress:
   `tests/fixtures/gcode/nurbs_g5_semantics.ngc` and
   `tests/fixtures/canon/nurbs_g5_semantics.events` pin `G5.2` control-point
   collection and `G5.3` NURBS feed emission.
+- `runtime/core/linuxcnc_wrap/linuxcnc_interp_minimal_runtime.cpp` now records
+  NURBS G6 canonical boundary calls emitted by vendored
+  `interp_convert.cc::convert_nurbs()`: `NURBS_G6_FEED`.
+  `tests/fixtures/gcode/nurbs_g6_semantics.ngc` and
+  `tests/fixtures/canon/nurbs_g6_semantics.events` pin `G6.2` order,
+  interpolation mode, control-point, weight, and K segment handling.
 - `tests/fixtures/gcode_errors/g1_zero_feed.ngc` and
   `tests/fixtures/canon_errors/g1_zero_feed.expected` pin the negative
   `G1` zero-feed case. The source basis is LinuxCNC

wasm-port/runtime/core/linuxcnc_wrap/linuxcnc_interp_minimal_runtime.cpp

@@ -471,7 +471,30 @@ void NURBS_G5_FEED(int lineno,
     }
     standalone::push_canon_event(oss.str());
 }
-void NURBS_G6_FEED(int, const std::vector<NURBS_G6_CONTROL_POINT> &, unsigned int, double, int, CANON_PLANE) {}
+void NURBS_G6_FEED(int lineno,
+                   const std::vector<NURBS_G6_CONTROL_POINT> &control_points,
+                   unsigned int k,
+                   double feedrate,
+                   int interpolation_mode,
+                   CANON_PLANE plane)
+{
+    std::ostringstream oss;
+    oss << "NURBS_G6_FEED line=" << lineno
+        << " k=" << k
+        << " feedrate=" << feedrate
+        << " interpolation_mode=" << interpolation_mode
+        << " plane=" << static_cast<int>(plane)
+        << " points=" << control_points.size();
+    for (std::size_t index = 0; index < control_points.size(); ++index) {
+        const auto &point = control_points[index];
+        oss << " p" << index
+            << "=(" << point.NURBS_X
+            << "," << point.NURBS_Y
+            << "," << point.NURBS_R
+            << "," << point.NURBS_K << ")";
+    }
+    standalone::push_canon_event(oss.str());
+}
 
 void COMMENT(const char *s)
 {

wasm-port/tests/fixtures/canon/nurbs_g6_semantics.events

@@ -0,0 +1,4 @@
+canon_event=SELECT_PLANE plane=1
+canon_event=STRAIGHT_TRAVERSE line=1 x=0 y=0 z=0 a=0 b=0 c=0 u=0 v=0 w=0
+canon_event=SET_FEED_RATE rate=50
+canon_event=NURBS_G6_FEED line=5 k=2 feedrate=50 interpolation_mode=1 plane=1 points=3 p0=(0,0,1,0) p1=(1,0,1,1) p2=(1,1,1,1)

wasm-port/tests/fixtures/gcode/nurbs_g6_semantics.ngc

@@ -0,0 +1,5 @@
+G90 G17 G0 X0 Y0 Z0
+F50
+G6.2 P2 Q1 X0 Y0 R1 K0
+G6.2 X1 Y0 R1 K1
+G6.2 X1 Y1 R1 K1