[Bug target/79793] Incorrect stack alignment for interrupt handler in 64-bit

[hjl.tools at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79793

H.J. Lu <hjl.tools at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|RESOLVED                    |REOPENED
   Last reconfirmed|                            |2017-03-13
         Resolution|FIXED                       |---
     Ever confirmed|0                           |1

--- Comment #5 from H.J. Lu <hjl.tools at gmail dot com> ---
In 64-bit mode, stack is 16-byte aligned when entering handler.  But if
there is error code

SS
RSP
FLAGS
CS
RIP
Error Code

the stack alignment is off by 8 bytes.  That is %rsp + 8 isn't multiple
of 16 at the start of handler.