Merge branch 'x86-build-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 build bits from Peter Anvin:
 "Various build-related minor bits.

  Most of this is work by David Woodhouse to be able to compile the
  early boot code with clang/llvm; we have also managed to push an
  actual -m16 option into gcc 4.9 so this makes us use that option if
  available instead of hacking it.

  The balance is a patch from Michael Davidson to the relocs program to
  help manual debugging.

  None of these should change the actual compiled binary with currently
  released compilers"

* 'x86-build-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, build: Build 16-bit code with -m16 where possible
  x86, boot: Fix word-size assumptions in has_eflag() inline asm
  x86, boot: Use __attribute__((used)) to ensure videocard structs are emitted
  x86: Remove duplication of 16-bit CFLAGS
  x86, relocs: Add manual debug mode

1 files changed, 20 insertions, 5 deletions

diff --git a/arch/x86/boot/cpuflags.c b/arch/x86/boot/cpuflags.c
index a9fcb7cfb241..431fa5f84537 100644
--- a/arch/x86/boot/cpuflags.c
+++ b/arch/x86/boot/cpuflags.c
@@ -28,20 +28,35 @@ static int has_fpu(void)
 	return fsw == 0 && (fcw & 0x103f) == 0x003f;
 }
 
+/*
+ * For building the 16-bit code we want to explicitly specify 32-bit
+ * push/pop operations, rather than just saying 'pushf' or 'popf' and
+ * letting the compiler choose. But this is also included from the
+ * compressed/ directory where it may be 64-bit code, and thus needs
+ * to be 'pushfq' or 'popfq' in that case.
+ */
+#ifdef __x86_64__
+#define PUSHF "pushfq"
+#define POPF "popfq"
+#else
+#define PUSHF "pushfl"
+#define POPF "popfl"
+#endif
+
 int has_eflag(unsigned long mask)
 {
 	unsigned long f0, f1;
 
-	asm volatile("pushf	\n\t"
-		     "pushf	\n\t"
+	asm volatile(PUSHF "	\n\t"
+		     PUSHF "	\n\t"
 		     "pop %0	\n\t"
 		     "mov %0,%1	\n\t"
 		     "xor %2,%1	\n\t"
 		     "push %1	\n\t"
-		     "popf	\n\t"
-		     "pushf	\n\t"
+		     POPF "	\n\t"
+		     PUSHF "	\n\t"
 		     "pop %1	\n\t"
-		     "popf"
+		     POPF
 		     : "=&r" (f0), "=&r" (f1)
 		     : "ri" (mask));