https://issues.dlang.org/show_bug.cgi?id=22896

          Issue ID: 22896
           Summary: importC: 'function redeclaration with different type'
                    should ignore const
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Keywords: ImportC, rejects-valid
          Severity: normal
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: duser@neet.fi

void fn(int);
void fn(const int x)
{
}

Error: function `fn` redeclaration with different type

gcc and clang allow this without warnings

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