[Bug c++/88003] New: ICE on outside definition of inner function-local class in poplevel_class, at cp/name-lookup.c:4325

["eugvelesevich at gmail dot com" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88003

            Bug ID: 88003
           Summary: ICE on outside definition of inner function-local
                    class in poplevel_class, at cp/name-lookup.c:4325
           Product: gcc
           Version: 9.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: eugvelesevich at gmail dot com
  Target Milestone: ---

Source:
auto test() {
  struct O { 
    struct N;
  };  
  return O();
}

struct decltype(test())::N {};

Output:
g++ -std=c++14 -S -x c++ -
source>:8:29: internal compiler error: in poplevel_class, at
cp/name-lookup.c:2931
 struct decltype(test())::N {};
                             ^
All gcc versions supporting c++14 crash.

I'm not sure that decltype usage in this place is correct, but it can be
replaced with:
typedef decltype(test()) TN;
struct TN::N {};

Could be related to bug #84691?