[Bug c/68657] New: [6 Regression] "gcc -Werror=sign-conversion test.i" shows invalid: -Wsign-conversion is not an option that controls warnings

[burnus at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68657

            Bug ID: 68657
           Summary: [6 Regression] "gcc -Werror=sign-conversion test.i"
                    shows invalid: -Wsign-conversion is not an option that
                    controls warnings
           Product: gcc
           Version: 6.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
          Assignee: unassigned at gcc dot gnu.org
          Reporter: burnus at gcc dot gnu.org
  Target Milestone: ---

Using  touch test.ii test.i  with
  gcc -Werror=sign-conversion test.i
or
  g++ -Werror=sign-conversion test.i
shows:

cc1plus: error: -Werror=sign-conversion: -Wsign-conversion is not an option
that controls warnings


Using GCC 5 it works.

In  gcc/c-family/c.opt, one has:

Wsign-conversion
C ObjC C++ ObjC++ Var(warn_sign_conversion) LangEnabledBy(C ObjC,Wconversion)
Warn for implicit type conversions between signed and unsigned integers.