Subject: Re: linux-next: Tree for Apr 6 (arch/x86/mm/init_64.c)

From: Randy Dunlap <[email-masked]>
Date: Tue, 6 Apr 2021 11:32:37 -0700

On 4/6/21 5:31 AM, Stephen Rothwell wrote:
> Hi all,
> Changes since 20210401:

on x86_64:
# CONFIG_SPARSEMEM_VMEMMAP is not set

gcc (SUSE Linux) 7.5.0

../arch/x86/mm/init_64.c: In function 'remove_pmd_table':
../arch/x86/mm/init_64.c:1127:8: error: implicit declaration of function 'vmemmap_pmd_is_unused'; did you mean 'vmemmap_pmd_populate'? [-Werror=implicit-function-declaration]
        vmemmap_pmd_is_unused(addr, next)) {
        ^~~~~~~~~~~~~~~~~~~~~
        vmemmap_pmd_populate

Looks like that compound "if" is too much for gcc 7.5.0 to handle:

			} else if (IS_ENABLED(CONFIG_SPARSEMEM_VMEMMAP) &&
				   vmemmap_pmd_is_unused(addr, next)) {
					free_hugepage_table(pmd_page(*pmd),
							    altmap);
					spin_lock(&init_mm.page_table_lock);
					pmd_clear(pmd);
					spin_unlock(&init_mm.page_table_lock);
			}

-- 
~Randy
Reported-by: Randy Dunlap <[email-masked]>