diff --git a/board/samsung/smdk5422/smc.c b/board/samsung/smdk5422/smc.c
index 36dc9f74fb2..6809b55950c 100644
--- a/board/samsung/smdk5422/smc.c
+++ b/board/samsung/smdk5422/smc.c
@@ -22,7 +22,7 @@ static inline u32 exynos_smc(u32 cmd, u32 arg1, u32 arg2, u32 arg3)
 	register u32 reg3 __asm__("r3") = arg3;
 
 	__asm__ volatile (
-#if __GNUC__ >= 4 && __GNUC_MINOR__ >= 6
+#if __GNUC__ >= 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6)
 		".arch_extension sec\n"
 #endif
 		"smc	0\n"
@@ -39,7 +39,7 @@ static inline u32 exynos_smc_read(u32 cmd)
 	register u32 reg1 __asm__("r1") = 0;
 
 	__asm__ volatile (
-#if __GNUC__ >= 4 && __GNUC_MINOR__ >= 6
+#if __GNUC__ >= 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6)
 		".arch_extension sec\n"
 #endif
 		"smc	0\n"
diff --git a/config.mk b/config.mk
index 3dcea6a8f99..6bb826efae4 100644
--- a/config.mk
+++ b/config.mk
@@ -233,7 +233,7 @@ CFLAGS := $(CPPFLAGS) -Wall -Wstrict-prototypes
 endif
 
 CFLAGS_SSP := $(call cc-option,-fno-stack-protector)
-CFLAGS += $(CFLAGS_SSP)
+CFLAGS += $(CFLAGS_SSP) -std=gnu89
 # Some toolchains enable security related warning flags by default,
 # but they don't make much sense in the u-boot world, so disable them.
 CFLAGS_WARN := $(call cc-option,-Wno-format-nonliteral) \
diff --git a/include/linux/compiler-gcc5.h b/include/linux/compiler-gcc5.h
new file mode 100644
index 00000000000..96c77d79e29
--- /dev/null
+++ b/include/linux/compiler-gcc5.h
@@ -0,0 +1,52 @@
+#ifndef __LINUX_COMPILER_H
+#error "Please don't include <linux/compiler-gcc4.h> directly, include <linux/compiler.h> instead."
+#endif
+
+/* GCC 4.1.[01] miscompiles __weak */
+#ifdef __KERNEL__
+# if __GNUC_MINOR__ == 1 && __GNUC_PATCHLEVEL__ <= 1
+#  error Your version of gcc miscompiles the __weak directive
+# endif
+#endif
+
+#define __used			__attribute__((__used__))
+#define __must_check 		__attribute__((warn_unused_result))
+#define __compiler_offsetof(a,b) __builtin_offsetof(a,b)
+#define __always_inline		inline __attribute__((always_inline))
+
+/*
+ * A trick to suppress uninitialized variable warning without generating any
+ * code
+ */
+#define uninitialized_var(x) x = x
+
+/* Mark functions as cold. gcc will assume any path leading to a call
+   to them will be unlikely.  This means a lot of manual unlikely()s
+   are unnecessary now for any paths leading to the usual suspects
+   like BUG(), printk(), panic() etc. [but let's keep them for now for
+   older compilers]
+
+   Early snapshots of gcc 4.3 don't support this and we can't detect this
+   in the preprocessor, but we can live with this because they're unreleased.
+   Maketime probing would be overkill here.
+
+   gcc also has a __attribute__((__hot__)) to move hot functions into
+   a special section, but I don't see any sense in this right now in
+   the kernel context */
+#define __cold			__attribute__((__cold__))
+
+
+/*
+ * Mark a position in code as unreachable.  This can be used to
+ * suppress control flow warnings after asm blocks that transfer
+ * control elsewhere.
+ *
+ * Early snapshots of gcc 4.5 don't support this and we can't detect
+ * this in the preprocessor, but we can live with this because they're
+ * unreleased.  Really, we need to have autoconf for the kernel.
+ */
+#define unreachable() __builtin_unreachable()
+
+#define __compiletime_object_size(obj) __builtin_object_size(obj, 0)
+#define __compiletime_warning(message) __attribute__((warning(message)))
+#define __compiletime_error(message) __attribute__((error(message)))