[Bug c/64862] printf attribute should accept other string types

[joseph at codesourcery dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64862

--- Comment #4 from joseph at codesourcery dot com <joseph at codesourcery dot com> ---
Note also that gcc.dg/format tests are run both with and without -DWIDE - 
the intent there is that wide string formats should be tested, when 
supported, with essentially the same tests as narrow string formats (via 
appropriate macros to make the tests generic, e.g. wrapping format strings 
in a macro L()).  That could be applied to other string types as well by 
running the tests more than twice.