Re: [PATCH] x86/kbuild: enable modversions for symbols exported from asm

Michal Marek
2016-12-14T10:15:10Z

On 2016-12-14 11:02, Dodji Seketeli wrote:
> Michal Marek <mmarek@suse.com> a écrit:
>
>>> Libabigail does a "whole binary" analysis of types.
>>>
>>> So, consider the point of use of the type 'struct s1*'. Even if 'struct
>>> s' is just forward-declared at that point, the declaration of struct s1
>>> is "resolved" to its definition. Even if the definition comes later in
>>> the binary.
>>
>> But there isn't any definition of struct s1 in t1.o. Does abidiff
>> "steal" the definition from the other object file? That would be
>> legitimate, I'm just curious.
>
> If there is another translation unit in the *same* binary that defines
> struct s1, then yes, it's "stolen", as you say.
>
> But if in the entire binary, struct s1 is just declared (not defined),
> then it'll compare equal to any struct s1 that is defined in the
> *second* binary.

That makes sense, thanks.

Michal