Move macro QEMU_GNUC_PREREQ to compiler.h

The macro is compiler specific and does not depend on the operating system.

Move macro QEMU_GNUC_PREREQ from osdep.h to compiler.h
and use it to simplify existing code.

host-utils.h uses this macro, so it now needs compiler.h
instead of osdep.h.
Signed-off-by: NStefan Weil <weil@mail.berlios.de>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

compiler.h

@@ -5,7 +5,19 @@
 
 #include "config-host.h"
 
+/*----------------------------------------------------------------------------
+| The macro QEMU_GNUC_PREREQ tests for minimum version of the GNU C compiler.
+| The code is a copy of SOFTFLOAT_GNUC_PREREQ, see softfloat-macros.h.
+*----------------------------------------------------------------------------*/
+#if defined(__GNUC__) && defined(__GNUC_MINOR__)
+# define QEMU_GNUC_PREREQ(maj, min) \
+         ((__GNUC__ << 16) + __GNUC_MINOR__ >= ((maj) << 16) + (min))
+#else
+# define QEMU_GNUC_PREREQ(maj, min) 0
+#endif
+
 #define QEMU_NORETURN __attribute__ ((__noreturn__))
+
 #ifdef CONFIG_GCC_ATTRIBUTE_WARN_UNUSED_RESULT
 #define QEMU_WARN_UNUSED_RESULT __attribute__((warn_unused_result))
 #else
@@ -22,8 +34,7 @@
     typedef char qemu_build_bug_on__##__LINE__[(x)?-1:1];
 
 #if defined __GNUC__
-# if (__GNUC__ < 4) || \
-     defined(__GNUC_MINOR__) && (__GNUC__ == 4) && (__GNUC_MINOR__ < 4)
+# if !QEMU_GNUC_PREREQ(4, 4)
    /* gcc versions before 4.4.x don't support gnu_printf, so use printf. */
 #  define GCC_ATTR __attribute__((__unused__, format(printf, 1, 2)))
 #  define GCC_FMT_ATTR(n, m) __attribute__((format(printf, n, m)))

host-utils.h

@@ -23,7 +23,7 @@
  * THE SOFTWARE.
  */
 
-#include "osdep.h"
+#include "compiler.h"   /* QEMU_GNUC_PREREQ */
 
 #if defined(__x86_64__)
 #define __HAVE_FAST_MULU64__

osdep.h

@@ -81,13 +81,6 @@
 
 #define qemu_printf printf
 
-#if defined (__GNUC__) && defined (__GNUC_MINOR__)
-# define QEMU_GNUC_PREREQ(maj, min) \
-         ((__GNUC__ << 16) + __GNUC_MINOR__ >= ((maj) << 16) + (min))
-#else
-# define QEMU_GNUC_PREREQ(maj, min) 0
-#endif
-
 int qemu_daemon(int nochdir, int noclose);
 void *qemu_memalign(size_t alignment, size_t size);
 void *qemu_vmalloc(size_t size);