---

yaml --- r: 169089 b: refs/heads/master c: 38938c8 h: refs/heads/master i: 169087: 296244d v: v3
git-mirror · Dec 5, 2009 · 3a2c02f · 3a2c02f
1 parent 70c35f5
commit 3a2c02f
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Showing 3 changed files with 20 additions and 1 deletion.
diff --git a/[refs] b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 22763c5cf3690a681551162c15d34d935308c8d7
+refs/heads/master: 38938c879eb0c39edf85d5164aa0cffe2874304c
diff --git a/trunk/include/linux/compiler-gcc4.h b/trunk/include/linux/compiler-gcc4.h
@@ -36,4 +36,18 @@
    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
diff --git a/trunk/include/linux/compiler.h b/trunk/include/linux/compiler.h
@@ -144,6 +144,11 @@ void ftrace_likely_update(struct ftrace_branch_data *f, int val, int expect);
 # define barrier() __memory_barrier()
 #endif
 
+/* Unreachable code */
+#ifndef unreachable
+# define unreachable() do { } while (1)
+#endif
+
 #ifndef RELOC_HIDE
 # define RELOC_HIDE(ptr, off)					\
   ({ unsigned long __ptr;					\