[Bug target/59927] [4.9 Regression] ICE sorry, unimplemented: ms_abi attribute requires -maccumulate-outgoing-args or subtarget optimization implying it

[rth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59927

Richard Henderson <rth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |ASSIGNED
           Assignee|unassigned at gcc dot gnu.org      |rth at gcc dot gnu.org

--- Comment #6 from Richard Henderson <rth at gcc dot gnu.org> ---
Created attachment 32080
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=32080&action=edit
testing patch

Here's a patch that seems altogether too straightforward.

It suppresses the incorrect first adjustment mentioned in the previous
comment while retaining the reg_parm_stack_space adjust.

I also tested the obvious 5 argument call and see

    subq    $8, %rsp
    pushq    $4
    subq    $32, %rsp
    movl    $3, %r9d
    movl    $2, %r8d
    movl    $1, %edx
    movl    $0, %ecx
    call    baz

which seems inefficient, but is also correct.

I'll attempt to test this at some point this weekend, but I'm not
currently in a position to build on x86_64 windows.  Kai, can you
fire something off?