https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78146
Bug ID: 78146 Summary: "-std=c++11 -std=gnu++11" is different from "-std=gnu++11" alone Product: gcc Version: 6.2.1 Status: UNCONFIRMED Severity: normal Priority: P3 Component: other Assignee: unassigned at gcc dot gnu.org Reporter: Laurent.Rineau__gcc at normalesup dot org Target Milestone: --- Let say I have this file with one line: auto v = 1.Q; That file does compile with `g++ -std=gnu++11 -c test.cpp`, but not with `g++ -std=c++11 -std=gnu++11 -c test.cpp` (when `-std=` is used twice): g++ -std=c++11 -std=gnu++11 -c test.cpp test.cpp:1:10: error: unable to find numeric literal operator ‘operator""Q’ auto v = 1.Q; ^~~ test.cpp:1:10: note: use -std=gnu++11 or -fext-numeric-literals to enable more built-in suffixes Compilation exited abnormally with code 1 at Fri Oct 28 13:47:10 Should not the last `-std=` supersede completely any previous occurrence? I use gcc from Fedora 24: gcc (GCC) 6.2.1 20160916 (Red Hat 6.2.1-2)