[Bug c/57137] New: spurious "format string is not literal" when the format string is marked with __attribute__((format))

[zbyszek at in dot waw.pl]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57137

             Bug #: 57137
           Summary: spurious "format string is not literal" when the
                    format string is marked with __attribute__((format))
    Classification: Unclassified
           Product: gcc
           Version: 4.8.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: zbyszek@in.waw.pl


If the format string is marked as a printf format with an attribute
format((printf(...)) on the wrapper function, then gcc should know that it's
either a valid printf format, or will be warned about at the point
where it is passed to the wrapper function, and shouldn't warn that
the format string is not a literal.

Attached example gives:
unit.c: In function ‘unit_status_printf’:
unit.c:6:9: warning: format not a string literal, argument types not checked
[-Wformat-nonliteral]
         manager_status_printf(status, unit_status_msg_format, "xxx");
         ^

It is possible to work around by placing #pragma GCC diagnostic ignored
"-Wformat-nonliteral" before the function, but that feels like a kludge.