[grsec] strange difference in latest patch

[Carlos Carvalho]

Running
interdiff grsecurity-2.1.14-2.6.29.6-200908140946.patch grsecurity-2.1.14-2.6.29.6-200908252018.patch

I get

+++ linux-2.6.29.6/arch/x86/include/asm/pgtable_32.h    2009-08-25 20:18:16.685282685 -0400
@@ -48,7 +48,10 @@
 #ifdef CONFIG_X86_PAE
 extern pmd_t swapper_pm_dir[PTRS_PER_PGD][PTRS_PER_PMD];
 #endif
-extern pte_t swapper_pg_fixmap[PTRS_PER_PMD];
+extern pte_t swapper_pg_fixmap0[PTRS_PER_PMD];
+extern pte_t swapper_pg_fixmap1[PTRS_PER_PMD];
+extern pte_t swapper_pg_fixmap2[PTRS_PER_PMD];
+extern pte_t swapper_pg_fixmap3[PTRS_PER_PMD];

However these are not referenced anywhere in the rest of the (small)
changes between the two versions. I have no idea what
swapper_pg_fixmap* means but I'd expect them to be referenced
somewhere. This patch gives the impression that it's not finished. Or
is it a bug in interdiff?