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

[emsr at gcc dot gnu.org]

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

--- Comment #3 from emsr at gcc dot gnu.org ---
I've got a simple fix.
I can verify that it works but how do you run the testsuite for c++11?