tests/gc/gcleak4.nim

lib/system/debugger.nim

@@ -632,7 +632,12 @@ proc genericHashAux(dest: Pointer, mt: PNimType, shallow: bool,
     else:
       result = h
       var s = cast[ppointer](dest)[]
-      if s != nil: result = genericHashAux(s, mt.base, shallow, result)
+      if s != nil:
+        result = result !& genericHashAux(s, mt.base, shallow, result)
+        # hash the object header:
+        #const headerSize = sizeof(int)*2
+        #result = result !& hash(cast[pointer](cast[int](s) -% headerSize),
+        #                        headerSize)
   else:
     result = h !& hash(dest, mt.size) # hash raw bits
 

lib/system/gc.nim

@@ -100,6 +100,8 @@ proc usrToCell(usr: pointer): PCell {.inline.} =
   result = cast[PCell](cast[TAddress](usr)-%TAddress(sizeof(TCell)))
 
 proc canbeCycleRoot(c: PCell): bool {.inline.} =
+  if c.typ == nil:
+    echo "ARRGHHHHHHH"
   result = ntfAcyclic notin c.typ.flags
 
 proc extGetCellType(c: pointer): PNimType {.compilerproc.} =