http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48760
--- Comment #29 from Paolo Carlini <paolo.carlini at oracle dot com> 2011-04-29 23:24:19 UTC --- This is now fixed in 4_6-branch too in C++03 mode, not in C++0x mode, where we would need list-initialization of __complex__. If people believe we can / should do something else in the release branch, I'm all ears: if for example people consider a better trade-off for the branch removing the constexpr from the constructor in order to initialized in the body for C++0x mode too, I'm ok with that.