[Bug target/61296] Excessive alignment in ix86_data_alignment

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61296

--- Comment #9 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
(In reply to H.J. Lu from comment #8)
> Do you have a testcase to show decreasing DATA_ALIGNMENT would break
> backwards compatibility with older gcc versions?

Older GCC versions used DATA_ALIGNMENT (what is now DATA_ABI_ALIGNMENT) on
MEM_ALIGN etc., and gradually more and more optimizations relied on it, even
when the data was defined in some other compilation unit or was comdat or could
be interposed.  See e.g. https://gcc.gnu.org/bugzilla/show_bug.cgi?id=56564#c9