[Bug c/93474] New: no warning for nonstandard bit field

[doug at cs dot dartmouth.edu]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93474

            Bug ID: 93474
           Summary: no warning for nonstandard bit field
           Product: gcc
           Version: 7.4.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
          Assignee: unassigned at gcc dot gnu.org
          Reporter: doug at cs dot dartmouth.edu
  Target Milestone: ---

struct { char x:1; } is implementation-defined syntax
per www.open-std.org/jtc1/sc22/wg14/www/docs/n2433.pdf,
Section 6.7.2.1, Constraint 5, which requires support
of only _Bool, signed int and unsigned int declarators.

gcc -Wall -Wpedantic -Wextra  does not report this
nonstandard usage.