[Bug c++/83756] gcc (mingw64) 7.2.0 ICE on boost::call_once

[jacobgodserv at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83756

--- Comment #2 from Jacob Godserv <jacobgodserv at gmail dot com> ---
Created attachment 43077
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=43077&action=edit
Minimal test case

With:
x86_64-w64-mingw32-g++ -std=c++11 -I path/to/official/boost/1.57/includes/ -L
path/to/official/boost/1.57/64bit/libraries/ TestClass.cpp

I am able to reproduce the failure. See the attached file for the minimal test
case.