Re: [PATCH 20/24] objtool: Another static block fail

[Josh Poimboeuf]

On Tue, Jan 23, 2018 at 04:25:59PM +0100, Peter Zijlstra wrote:
> I've observed GCC generate:
> 
>   sym:
>      NOP/JMP 1f	(static_branch)
>      JMP 2f
>   1: /* crud */
>      JMP 3f
>   2: /* other crud */
> 
>   3: RETQ
> 
> 
> This means we need to follow unconditional jumps; be conservative and
> only follow if its a unique jump.
> 
> (I've not yet figured out which CONFIG option is responsible for this,
>  a normal defconfig build does not generate crap like this)
> 
> Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>

Any chance we can just add a compiler barrier to the assertion macro and
avoid all this grow_static_blocks() mess?  It seems a bit... fragile.

-- 
Josh