https://issues.dlang.org/show_bug.cgi?id=21967

          Issue ID: 21967
           Summary: importC: Error function without 'this' cannot be
                    'const'
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: major
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: ibuclaw@gdcproject.org

When declaring a function that returns a const result.
---
const int const_int_fn(void);
const int *const_int_fnptr(void);
const int **const_int_fnptrptr(void);

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