On 12/10/20 2:47 PM, marcandre.lureau@redhat.com wrote:
From: Marc-André Lureau <marcandre.lureau@redhat.com>
Since commit efc6c07 ("configure: Add a test for the minimum compiler
version"), QEMU explicitely depends on GCC >= 4.8.
(clang >= 3.4 advertizes itself as GCC >= 4.2 compatible and supports
__builtin_expect too)
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
---
include/qemu/compiler.h | 4 ----
1 file changed, 4 deletions(-)
diff --git a/include/qemu/compiler.h b/include/qemu/compiler.h
index c76281f354..226ead6c90 100644
--- a/include/qemu/compiler.h
+++ b/include/qemu/compiler.h
@@ -44,10 +44,6 @@
#endif
#ifndef likely
-#if __GNUC__ < 3
-#define __builtin_expect(x, n) (x)
-#endif
-
#define likely(x) __builtin_expect(!!(x), 1)
#define unlikely(x) __builtin_expect(!!(x), 0)
#endif
Trying with GCC 10:
warning: implicit declaration of function ‘likely’
[-Wimplicit-function-declaration]
Clang 10:
warning: implicit declaration of function 'likely' is invalid in C99
[-Wimplicit-function-declaration]
Shouldn't it becleaner to test in the configure script or Meson that
likely() and unlikely() are not defined, and define them here
unconditionally?