diff --git a/mm/memblock.c b/mm/memblock.c
index b7ed63633581..7d4f5c8a96cb 100644
--- a/mm/memblock.c
+++ b/mm/memblock.c
@@ -267,7 +267,7 @@ static int __init_memblock memblock_double_array(struct memblock_type *type)
 	return 0;
 }
 
-extern int __init_memblock __weak memblock_memory_can_coalesce(phys_addr_t addr1, phys_addr_t size1,
+int __init_memblock __weak memblock_memory_can_coalesce(phys_addr_t addr1, phys_addr_t size1,
 					  phys_addr_t addr2, phys_addr_t size2)
 {
 	return 1;