Re: [akpm-mm:mm-new 429/433] mm/swap_state.c:468:19: error: call to undeclared function 'folio_memcg_alloc_deferred'; ISO C99 and later do not support implicit function declarations

[Johannes Weiner <hannes@cmpxchg.org>]

On Thu, May 28, 2026 at 03:16:18PM -0700, Andrew Morton wrote:
> On Thu, 28 May 2026 16:15:31 +0800 kernel test robot <lkp@intel.com> wrote:
> 
> > tree:   https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-new
> > head:   d7d405cc33d6e3eeba2d6ec8f0b595da2a5c600a
> > commit: a5e62d9e00dac6f96174c397a82da30e7ae53064 [429/433] mm: switch deferred split shrinker to list_lru
> > config: hexagon-defconfig (https://download.01.org/0day-ci/archive/20260528/202605281620.lc3rtkBm-lkp@intel.com/config)
> > compiler: clang version 23.0.0git (https://github.com/llvm/llvm-project 9409c07de6378507397ecdb6f05f628f58110112)
> > reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260528/202605281620.lc3rtkBm-lkp@intel.com/reproduce)
> > 
> > If you fix the issue in a separate patch/commit (i.e. not just a new version of
> > the same patch/commit), kindly add following tags
> > | Reported-by: kernel test robot <lkp@intel.com>
> > | Closes: https://lore.kernel.org/oe-kbuild-all/202605281620.lc3rtkBm-lkp@intel.com/
> > 
> > All errors (new ones prefixed by >>):
> > 
> > >> mm/swap_state.c:468:19: error: call to undeclared function 'folio_memcg_alloc_deferred'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
> >      468 |         if (order > 1 && folio_memcg_alloc_deferred(folio)) {
> >          |                          ^
> >    1 error generated.
> 
> Thanks.  How does this look?
> 
> 
> From: Andrew Morton <akpm@linux-foundation.org>
> Subject: mm-switch-deferred-split-shrinker-to-list_lru-fix
> Date: Thu May 28 03:12:45 PM PDT 2026
> 
> fix build with CONFIG_TRANSPARENT_HUGEPAGE=n

Thanks! SJ also sent a fix to this end. Either of them will work :)