http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59867
--- Comment #2 from Jakub Jelinek <jakub at gcc dot gnu.org> --- This looks just as a missed diagnostics of invalid source. Both in C++11 and in n3690 there is in [over.literal]/5: "The declaration of a literal operator template shall have an empty parameter-declaration-clause and its template-parameter-list shall have a single template-parameter that is a non-type template parameter pack (14.5.3) with element type char."
