https://issues.dlang.org/show_bug.cgi?id=16627

          Issue ID: 16627
           Summary: [Reg 2.072] struct with disabled postblit field is now
                    nested
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: regression
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: code@dawg.eu

cat > bug.d << CODE
void bug(A...)(ref A args)
{
    struct S { A expand; } // no references
    static assert(!__traits(isNested, S)); // suddenly nested
}

struct SNoCopy
{
    @disable this(this);
}

void test()
{
    SNoCopy itm;
    bug(itm);
}
CODE
dmd -c bug
----

Apparently caused by https://github.com/dlang/dmd/pull/5500.

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