Re: -rc3 leaking NOT BIO [Was: Memory leak in 2.6.11-rc1?]

[Parag Warudkar <kernel-stuff@comcast.net>]

On Wednesday 16 February 2005 10:48 pm, Horst von Brand wrote:
> Does x86_64 use up a (freeable) register for the frame pointer or not?
> I.e., does -fomit-frame-pointer have any effect on the generated code?

{Took Linus out of the loop as he probably isn't interested}

The generated code is different for both cases but for some reason gcc has 
trouble with __builtin_return_address on x86-64.

For e.g. specifying gcc -fo-f-p, a method produces following assembly.

method_1:
.LFB2:
        subq    $8, %rsp
.LCFI0:
        movl    $__FUNCTION__.0, %esi
        movl    $.LC0, %edi
        movl    $0, %eax
        call    printf
        movl    $0, %eax
        addq    $8, %rsp
        ret

And with -fno-o-f-p,  the same method yields 

method_1:
.LFB2:
        pushq   %rbp
.LCFI0:
        movq    %rsp, %rbp
.LCFI1:
        movl    $__FUNCTION__.0, %esi
        movl    $.LC0, %edi
        movl    $0, %eax
        call    printf
        movl    $0, %eax
        leave
        ret