fixes #23867; fixes #23316; rework nimsuggest for ORC (#23879)

fixes #23867
fixes #23316 


follow up https://github.com/nim-lang/Nim/pull/22805; fixes
https://github.com/nim-lang/Nim/issues/22794 in a different method

nimsuggest/nimsuggest.nim

@@ -231,6 +231,14 @@ proc clearInstCache(graph: ModuleGraph, projectFileIdx: FileIndex) =
   for id in procIdsToDelete:
     graph.procInstCache.del id
 
+  for tbl in mitems(graph.attachedOps):
+    var attachedOpsToDelete = newSeq[ItemId]()
+    for id in tbl.keys:
+      if id.module == projectFileIdx.int and sfOverridden in resolveAttachedOp(graph, tbl[id]).flags:
+        attachedOpsToDelete.add id
+    for id in attachedOpsToDelete:
+      tbl.del id
+
 proc executeNoHooks(cmd: IdeCmd, file, dirtyfile: AbsoluteFile, line, col: int, tag: string,
              graph: ModuleGraph) =
   let conf = graph.config
@@ -765,6 +773,10 @@ proc handleCmdLine(cache: IdentCache; conf: ConfigRef) =
 
   var graph = newModuleGraph(cache, conf)
   if self.loadConfigsAndProcessCmdLine(cache, conf, graph):
+
+    if conf.selectedGC == gcUnselected and
+          conf.backend != backendJs:
+      initOrcDefines(conf)
     mainCommand(graph)
 
 # v3 start

nimsuggest/tests/tchk2.nim

@@ -0,0 +1,35 @@
+# bug #22794
+type O = object
+
+proc `=destroy`(x: O) = discard
+proc `=trace`(x: var O; env: pointer) = discard
+proc `=copy`(a: var O; b: O) = discard
+proc `=dup`(a: O): O {.nodestroy.} = a
+proc `=sink`(a: var O; b: O) = discard
+
+
+# bug #23316
+type SomeSturct = object
+
+proc `=destroy`(x: SomeSturct) =
+  echo "SomeSturct destroyed"
+
+# bug #23867
+type ObjStr = object
+  s: string
+
+let ostr = ObjStr() # <-- nimsuggest crashes
+discard ostr
+
+type ObjSeq = object
+  s: seq[int]
+
+let oseq = ObjSeq() # <-- nimsuggest crashes
+discard oseq
+
+#[!]#
+discard """
+$nimsuggest --tester $file
+>chk $1
+chk;;skUnknown;;;;Hint;;???;;0;;-1;;">> (toplevel): import(dirty): tests/tchk2.nim [Processing]";;0
+"""