https://issues.dlang.org/show_bug.cgi?id=23802

          Issue ID: 23802
           Summary: ImportC: __volatile__ is yet another alias for
                    volatile
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: normal
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: dave287091@gmail.com

Several macOS headers use __volatile__ as in __asm__ __volatile__. As asm volatile can now be parsed, this causes errors in code that would other compile fine.

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