[Bug c/51628] __attribute__((packed)) is unsafe in some cases

[ebotcazou at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51628

--- Comment #14 from Eric Botcazou <ebotcazou at gcc dot gnu.org> 2011-12-20 17:43:07 UTC ---
> What Ada does looks just like a workaround for what should be done properly in
> the expander.  So no, IMHO we shouldn't be changing all other FEs and the
> middle-end (when it wants to generate them e.g. for memcpy) to do what Ada
> does, but we should change the expander.

Of course I have the exactly opposite viewpoint, since I think that we should
keep the invariants we have: integral modes are naturally aligned and
TYPE_ALIGN >= MODE_ALIGN (TYPE_MODE).  Breaking them for a few pathological
cases that the C compiler has shun for years doesn't seem the best course of
action.