https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67549
Richard Biener <rguenth at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|UNCONFIRMED |RESOLVED Known to work| |4.9.0 Resolution|--- |FIXED Known to fail| |4.8.5 --- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> --- With GCC 4.9 I need -fpermissive to even build on x86_64: > g++-4.9 -S t.C -std=c++11 t.C:6:42: error: ‘constexpr’ needed for in-class initialization of static data member ‘void (B::* B::ptr_func)(int)’ of non-integral type [-fpermissive] static T_PTRFUNC ptr_func = &B::elem_func; ^ with -fpermissive it works. I can reproduce the ICE on x86_64 with GCC 4.8.5. Thus I assume it is fixed with GCC 4.9 and up.