[Bug libstdc++/88341] [9 Regression] taking norm() of complex variable fails to compile with -std=c++11

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88341

--- Comment #4 from Jonathan Wakely <redi at gcc dot gnu.org> ---
make check RUNTESTFLAGS=--target_board=unix/-std=gnu++11