diff --git a/src/add-ons/kernel/bus_managers/acpi/ACPICAHaiku.cpp b/src/add-ons/kernel/bus_managers/acpi/ACPICAHaiku.cpp
index 68af7542ac2..00a05b73913 100644
--- a/src/add-ons/kernel/bus_managers/acpi/ACPICAHaiku.cpp
+++ b/src/add-ons/kernel/bus_managers/acpi/ACPICAHaiku.cpp
@@ -232,7 +232,7 @@ ACPI_PHYSICAL_ADDRESS
 AcpiOsGetRootPointer()
 {
 #ifdef _KERNEL_MODE
-	ACPI_SIZE address;
+	ACPI_PHYSICAL_ADDRESS address;
 	ACPI_STATUS status;
 	DEBUG_FUNCTION();
 	if (sACPIRoot == 0) {