[Bug target/38496] Gcc misaligns arrays when stack is forced follow the x8632 ABI

["hjl dot tools at gmail dot com" <gcc-bugzilla@gcc.gnu.org>]

------- Comment #9 from hjl dot tools at gmail dot com  2008-12-12 01:05 -------
(In reply to comment #8)
>
> This is a link where people mention that fact that gcc is behaving
> non-standardly, so people who want to interoperate with gcc better adopt their
> non-standard behavior.  How do you like it when MS does that?  It seems
> incredibly foolish to me that just because gcc doesn't want to do some trivial
> bit twiddling in the function prologue, you've decided to break the ABI, all so
> that you can lose performance when people need ABI compliance, as well as
> making interoperation much harder for everyone.
> 

It was a very unfortunate oversight to require 16byte stack alignment
while ABI only specifies 4 byte.  This problem has been fixed in gcc
4.4 and above. You can safely use -mpreferred-stack-boundary=2 with
gcc 4.4 and all stack variables will be properly aligned.  However,
we can't change the default back to 4 byte since it will break the
existing libraries/applications which expect 16byte aligned incoming
stack.


-- 

hjl dot tools at gmail dot com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |hjl dot tools at gmail dot
                   |                            |com
OtherBugsDependingO|                            |33721
              nThis|                            |
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|                            |WONTFIX


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38496