Re: [PATCH] mm: compaction: fix dummy declarations

[Andrew Morton]

On Wed, 15 Jun 2016 23:39:12 +0200 Arnd Bergmann <arnd@xxxxxxxx> wrote:

> We get a build error in several test builds after a recent code rework:
> 
> In file included from include/linux/balloon_compaction.h:48:0,
>                  from mm/balloon_compaction.c:11:
> include/linux/compaction.h:237:122: error: 'struct node' declared inside parameter list will not be visible outside of this definition or declaration [-Werror]
> 
> The patch that likely introduced the problem added a forward declaration
> for 'struct node' in linux/compaction.h, but only in one of two instances.
> 
> This moves the declaration out of the #ifdef so we always get it.

http://ozlabs.org/~akpm/mmots/broken-out/mm-balloon-use-general-non-lru-movable-page-feature-fix.patch
should fix this.  I guess I should do another -mm.