https://issues.dlang.org/show_bug.cgi?id=23879

          Issue ID: 23879
           Summary: ImportC: Windows system headers use `__alignof`
           Product: D
           Version: D2
          Hardware: All
                OS: Windows
            Status: NEW
          Keywords: ImportC
          Severity: normal
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: maxsamukha@gmail.com

struct S {
    int x;
};

int x = __alignof(struct S);

windows.c(7): Error: expression expected, not `struct

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