[Bug tree-optimization/67283] GCC regression over inlining of returned structures

[roche at httrack dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67283

--- Comment #10 from Xavier Roche <roche at httrack dot com> ---
The "Second test case" attached should produce exactly the same bytes
(byte-to-byte) for the two demo_1 and demo_2 functions. And this would not rely
on stack size that might change.

With GCC 4.4.7:

demo_2():
        subq    $72, %rsp
        movl    $0, 32(%rsp)
        movq    32(%rsp), %rax
        movq    $0, 48(%rsp)
        movq    $0, 40(%rsp)
        movq    $0, 8(%rsp)
        movq    $0, 16(%rsp)
        movq    %rax, (%rsp)
        call    some_unknown_function(foo)
        addq    $72, %rsp
        ret
demo_1():
        subq    $72, %rsp
        movl    $0, 32(%rsp)
        movq    32(%rsp), %rax
        movq    $0, 48(%rsp)
        movq    $0, 40(%rsp)
        movq    $0, 8(%rsp)
        movq    $0, 16(%rsp)
        movq    %rax, (%rsp)
        call    some_unknown_function(foo)
        addq    $72, %rsp
        ret