https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95143
--- Comment #8 from Bernd Baumanns <familiebaumanns at gmail dot com> --- fails with this version: g++ (Compiler-Explorer-Build) 10.1.0 Copyright (C) 2020 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. Compiler returned: 0 And this: g++-10 (Ubuntu 10-20200417-0ubuntu1) 10.0.1 20200417 (experimental) [master revision a64468a3034:28feadc0609:b835645c7a51b7e99092abe61d677aa491836f95] Copyright (C) 2020 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.