[m68k] Add patch to build with -ffreestanding to fix FTBFS

debian/changelog

@@ -1,3 +1,10 @@
+linux (4.19.13-2) UNRELEASED; urgency=medium
+
+  [ John Paul Adrian Glaubitz ]
+  * [m68k] Add patch to build with -ffreestanding to fix FTBFS
+
+ -- John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>  Sun, 30 Dec 2018 10:30:57 +0100
+
 linux (4.19.13-1) unstable; urgency=medium
 
   * New upstream stable update:

debian/patches/bugfix/m68k/m68k-build-with-ffreestanding.patch

@@ -0,0 +1,28 @@
+From: Finn Thain <fthain@telegraphics.com.au>
+Date: Fri, 21 Dec 2018 17:21:43 +1100 (AEDT)
+Subject: Build with -ffreestanding on m68k to avoid
+  risky optimizations involving libc
+Origin: https://marc.info/?l=linux-m68k&m=154537329920545&w=2
+
+diff --git a/arch/m68k/Makefile b/arch/m68k/Makefile
+index 997c9f20ea0f..c318afd15e33 100644
+--- a/arch/m68k/Makefile
++++ b/arch/m68k/Makefile
+@@ -58,1 +58,1 @@ cpuflags-$(CONFIG_M5206e)	:= $(call cc-option,-mcpu=5206e,-m5200)
+ cpuflags-$(CONFIG_M5206)	:= $(call cc-option,-mcpu=5206,-m5200)
+
+ KBUILD_AFLAGS += $(cpuflags-y)
+-KBUILD_CFLAGS += $(cpuflags-y) -pipe
++KBUILD_CFLAGS += $(cpuflags-y)
+ ifdef CONFIG_MMU
+ # without -fno-strength-reduce the 53c7xx.c driver fails ;-(
+ KBUILD_CFLAGS += -fno-strength-reduce -ffixed-a2
+@@ -69,2 +69,2 @@ KBUILD_CFLAGS += -D__uClinux__
+ KBUILD_AFLAGS += -D__uClinux__
+ endif
+
++KBUILD_CFLAGS += -pipe -ffreestanding
++
+ KBUILD_LDFLAGS := -m m68kelf
+ KBUILD_LDFLAGS_MODULE += -T $(srctree)/arch/m68k/kernel/module.lds
+

debian/patches/series

@@ -80,6 +80,7 @@ bugfix/x86/x86-32-disable-3dnow-in-generic-config.patch
 bugfix/x86/x86-mm-Fix-guard-hole-handling.patch
 bugfix/arm/gpio-mvebu-only-fail-on-missing-clk-if-pwm-is-actual.patch
 bugfix/powerpc/powerpc-fix-mcpu-options-for-spe-only-compiler.patch
+bugfix/m68k/m68k-build-with-ffreestanding.patch
 
 # Arch features
 features/mips/MIPS-increase-MAX-PHYSMEM-BITS-on-Loongson-3-only.patch