https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91464
Jonathan Wakely <redi at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|UNCONFIRMED |NEW Last reconfirmed| |2019-08-15 Ever confirmed|0 |1 --- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> --- The "2nd scenario" is: extern "C" namespace A { int value; } int getValue () { return A::value; } G++ only declares A::value, it doesn't define it.