https://issues.dlang.org/show_bug.cgi?id=21933

          Issue ID: 21933
           Summary: importC:
                    core.exception.AssertError@src/dmd/typesem.d(1890):
                    Assertion failure
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: critical
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: ibuclaw@gdcproject.org

Structs cannot be used as function parameters.

---
struct STRUCT { void *opaque; };
int fun(struct STRUCT *);
---

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