[Bug c++/68584] New: nested generic lambda with trailing return type cases compiler crash

["Gaetano.Checinski at gmail dot com" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68584

            Bug ID: 68584
           Summary: nested generic lambda with trailing return type cases
                    compiler crash
           Product: gcc
           Version: 6.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: Gaetano.Checinski at gmail dot com
  Target Milestone: ---

Created attachment 36856
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=36856&action=edit
backtrace

the following code causes a crash:

//auto F = [](auto){return 1; };
auto call = [](auto/*int*/) {
  auto F = [](auto){return 1; };
  return [=](auto /*int*/ x) -> decltype( F(x) ) { return F(x);};
};

int main(){
  call(1);
}


It has been tested with g++-5.2 and g++-6.0(20151122).
Might be related to bugID:66135 and bugID:61814