https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83342
Olivier Kannengieser <okannen at gmail dot com> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |okannen at gmail dot com --- Comment #2 from Olivier Kannengieser <okannen at gmail dot com> --- Whit gcc 8.2, there is no more bug for constant template variables. But compilation produces undefined symbol error at linking phase if variables templates are non const: template<class T> extern T value4; template<class T> T value4= 0; auto test4 = value4<int>; //linking phase error: undefined symbol value4<int> template<class T> extern T value5; template<class T> inline T value5=0; auto test5 = value5<int>; //linking phase error: undefined symbol value5<int> There are no error with Clang.