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[[!tag open_issue_mig]]


# IRC, freenode, #hurd, 2011-11-14

    <braunr> also, what's the best way to deal with types such as
    <braunr> type cache_info_t = struct[23] of integer_t;
    <braunr> whereas cache_info_t contains longs, which are obviously not
      integer-wide on 64-bits processors
    <braunr> ?
    <youpi> you mean, to port mach to 64bit?
    <braunr> no, to make the RPC declaration portable
    <braunr> just in case :)
    <youpi> refine integer_t into something more precise
    <youpi> such as size_t, off_t, etc.
    <braunr> i can't use a single line then
    <braunr> struct cache_info contains ints, vm_size_t, longs
    <braunr> should i just use the maximum size it can get ?
    <braunr> or declare two sizes depending on the word size ?
    <youpi> well, I'd say three
    <braunr> youpi: three ?
    <youpi> the ints, the vm_size_ts, and the longs
    <braunr> youpi: i don't get it
    <braunr> youpi: how would i write it in mig language ?
    <youpi> I don't know the mig language
    <braunr> me neither :)
    <youpi> but I'd say don't lie
    <braunr> i just see struct[23] of smething
    <braunr> the original zone_info struct includes both integer_t and
      vm_size_t, and declares it as
    <braunr> type zone_info_t = struct[9] of integer_t;
    <braunr> in its mig defs file
    <braunr> i don't have a good example to reuse
    <youpi> which is lying
    <braunr> yes
    <braunr> which is why i was wondering if mach architects themselves
      actually solved that problem :)
    <braunr> "There is no way to specify the fields of  a
    <braunr> C  structure  to  MIG. The size and type-desc are just used to
      give the size of
    <braunr> the structure.
    <braunr> "
    <braunr> well, this sucks :/
    <braunr> well, i'll do what the rest of the code seems to do, and let it
      rot until a viable solution is available
    <antrik> braunr: we discussed the problem of expressing structs with MIG in
      the libburn thread
    <antrik> (which I still need to follow up on... [sigh])