https://issues.dlang.org/show_bug.cgi?id=23064

          Issue ID: 23064
           Summary: wrong code generated for bitfield assignment to ?:
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: normal
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: bugzilla@digitalmars.com

The generated code is as if a.x and a.y were regular fields instead of bitfields.

struct A { int x: 3; int y: 5; } a;

struct A test(int val, int choice, struct A a)
{
    (choice ? a.x : a.y) = val;
    return a;
}

Affects D and ImportC.

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