ipv4: don't remove /proc/net/rt_acct

[safe/jmp/linux-2.6] / include / linux / compiler-gcc4.h

diff --git a/include/linux/compiler-gcc4.h b/include/linux/compiler-gcc4.h
index 77542c5..94dea3f 100644 (file)
--- a/include/linux/compiler-gcc4.h
+++ b/include/linux/compiler-gcc4.h
@@ -36,9 +36,25 @@
    the kernel context */
 #define __cold                 __attribute__((__cold__))
 
+
+#if __GNUC_MINOR__ >= 5
+/*
+ * 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()
 #endif
 
+#endif
+
+#if __GNUC_MINOR__ > 0
 #define __compiletime_object_size(obj) __builtin_object_size(obj, 0)
+#endif
 #if __GNUC_MINOR__ >= 4
 #define __compiletime_warning(message) __attribute__((warning(message)))
 #define __compiletime_error(message) __attribute__((error(message)))