diff options
authorMichael Davidson <>2017-07-24 16:51:55 -0700
committerIngo Molnar <>2017-07-25 11:13:55 +0200
commit18d5e6c34a8eda438d5ad8b3b15f42dab01bf05d (patch)
parent520eccdfe187591a51ea9ab4c1a024ae4d0f68d9 (diff)
x86/boot: #undef memcpy() et al in string.c
undef memcpy() and friends in boot/string.c so that the functions defined here will have the correct names, otherwise we end up up trying to redefine __builtin_memcpy() etc. Surprisingly, GCC allows this (and, helpfully, discards the __builtin_ prefix from the function name when compiling it), but clang does not. Adding these #undef's appears to preserve what I assume was the original intent of the code. Signed-off-by: Michael Davidson <> Signed-off-by: Matthias Kaehlcke <> Acked-by: H. Peter Anvin <> Cc: Arnd Bergmann <> Cc: Cc: Greg Hackmann <> Cc: Kees Cook <> Cc: Linus Torvalds <> Cc: Nick Desaulniers <> Cc: Peter Zijlstra <> Cc: Thomas Gleixner <> Link: Signed-off-by: Ingo Molnar <>
1 files changed, 9 insertions, 0 deletions
diff --git a/arch/x86/boot/string.c b/arch/x86/boot/string.c
index 630e3664906b..16f49123d747 100644
--- a/arch/x86/boot/string.c
+++ b/arch/x86/boot/string.c
@@ -16,6 +16,15 @@
#include "ctype.h"
#include "string.h"
+ * Undef these macros so that the functions that we provide
+ * here will have the correct names regardless of how string.h
+ * may have chosen to #define them.
+ */
+#undef memcpy
+#undef memset
+#undef memcmp
int memcmp(const void *s1, const void *s2, size_t len)
bool diff;