Summary: forward referenced inner struct with align(1) doesn't
                    add to offset of next field when used inside a union
                    of another struct, that is nested in the same outer
           Product: D
           Version: D2
          Platform: All
        OS/Version: Linux
            Status: NEW
          Keywords: wrong-code
          Severity: minor
          Priority: P2
         Component: DMD

--- Comment #0 from Marco Leise <> 2012-01-24 10:49:06 PST ---
This happened to me when I designed data structures for CD sectors, and used an
outer struct to wrap all the different sector layouts (Mode1/2 CDs, ...). The
short code below is more suited for a unittest:

    struct Outer {
        struct Inner1 {
            union { 
                Inner2 a;
            byte I_AM_AT_THE_WRONG_OFFSET;

        align(1) struct Inner2 {
            ubyte x;

    void main() {

This prints '0', which means that field 'I_AM_AT_THE_WRONG_OFFSET' wasn't
correctly offset behind field 'a'. It works correctly when
a) align(1) is removed
b) Inner2 is declared before Inner1
c) 'a' is not inside a union block

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