https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87038
--- Comment #11 from Steinar H. Gunderson <steinar+gcc at gunderson dot no> --- It is also not legal (side effects or not) when compiling as C++, which is one of the reasons for having this warning.
steinar+gcc at gunderson dot no Sun, 21 Oct 2018 10:20:02 -0700
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87038
--- Comment #11 from Steinar H. Gunderson <steinar+gcc at gunderson dot no> --- It is also not legal (side effects or not) when compiling as C++, which is one of the reasons for having this warning.