makes asmnostackframe work with cpp member #22411 (#22429)

compiler/cgen.nim

@@ -1142,7 +1142,8 @@ proc isNoReturn(m: BModule; s: PSym): bool {.inline.} =
 proc genProcAux*(m: BModule, prc: PSym) =
   var p = newProc(prc, m)
   var header = newRopeAppender()
-  if m.config.backend == backendCpp and sfCppMember * prc.flags != {}:
+  let isCppMember = m.config.backend == backendCpp and sfCppMember * prc.flags != {}
+  if isCppMember:
     genMemberProcHeader(m, prc, header)
   else:
     genProcHeader(m, prc, header)
@@ -1205,10 +1206,10 @@ proc genProcAux*(m: BModule, prc: PSym) =
   var generatedProc: Rope = ""
   generatedProc.genCLineDir prc.info, m.config
   if isNoReturn(p.module, prc):
-    if hasDeclspec in extccomp.CC[p.config.cCompiler].props:
+    if hasDeclspec in extccomp.CC[p.config.cCompiler].props and not isCppMember:
       header = "__declspec(noreturn) " & header
   if sfPure in prc.flags:
-    if hasDeclspec in extccomp.CC[p.config.cCompiler].props:
+    if hasDeclspec in extccomp.CC[p.config.cCompiler].props and not isCppMember:
       header = "__declspec(naked) " & header
     generatedProc.add ropecg(p.module, "$1 {$n$2$3$4}$N$N",
                          [header, p.s(cpsLocals), p.s(cpsInit), p.s(cpsStmts)])

tests/cpp/tvirtual.nim

@@ -79,3 +79,40 @@ type Doo = object
 proc naiveMember(x: Doo): int {. virtual .} = 2
 discard naiveMember(Doo())
 
+#asmnostackframe works with virtual
+{.emit:"""/*TYPESECTION*/
+  template<typename T>
+  struct Box {
+      T* first;
+     
+      Box(int x){
+        first = new T(x);
+      };
+  };
+  struct Inner {
+    int val;
+    //Coo() = default;
+    Inner(int x){
+      val = x;
+    };
+  };
+  struct Base {
+    virtual Box<Inner> test() = 0;
+  };
+""".}
+
+type 
+  Inner {.importcpp.} = object
+  Base {.importcpp, inheritable.} = object
+  Child  = object of Base
+  Box[T] {.importcpp, inheritable.} = object
+    first: T
+
+proc makeBox[T](x:int32): Box[T] {.importcpp:"Box<'0>(@)", constructor.}
+
+proc test(self: Child): Box[Inner] {.virtual, asmnostackframe.} = 
+  let res {.exportc.} = makeBox[Inner](100)
+  {.emit:"return res;".}
+  
+
+discard Child().test()