rp2040: fix -gc=leaking/none

src/runtime/gc_leaking.go

@@ -8,11 +8,16 @@ package runtime
 
 import (
 	"internal/task"
+	"sync/atomic"
 	"unsafe"
 )
 
 const needsStaticHeap = true
 
+var gcScanState atomic.Uint32
+
+func scanCurrentStack() {}
+
 // Ever-incrementing pointer: no memory is freed.
 var heapptr uintptr
 

src/runtime/gc_none.go

@@ -7,6 +7,7 @@ package runtime
 // targets that have far too little RAM even for the leaking memory allocator.
 
 import (
+	"sync/atomic"
 	"unsafe"
 )
 
@@ -15,6 +16,9 @@ const needsStaticHeap = false
 var gcTotalAlloc uint64 // for runtime.MemStats
 var gcMallocs uint64
 var gcFrees uint64
+var gcScanState atomic.Uint32
+
+func scanCurrentStack() {}
 
 func alloc(size uintptr, layout unsafe.Pointer) unsafe.Pointer