http://bugs.winehq.org/show_bug.cgi?id=22316
--- Comment #12 from Mike Frysinger vapier@gentoo.org 2011-07-12 11:03:34 CDT --- so even though the standard says "stack must be 16byte aligned", and gcc assumes the stack is 16byte aligned and will generate code that requires that (i.e. sse), you still don't care if wine breaks (as reported by various distros/users) ?
existing apps dont matter ... their stack isnt passed in. it's created fresh upon execution, so the change in ABI is irrelevant to them. if they work with 4byte alignment, and they only use 4byte alignment, then starting off with 16byte alignment changes nothing.
what matters here are newly compiled programs as that is where the code generation is coming from.