[Mesa-dev] [PATCH 1/2] mesa: Add unreachable macro.

[Matt Turner]

---
 src/mesa/main/compiler.h | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/src/mesa/main/compiler.h b/src/mesa/main/compiler.h
index 61ce5db..6a25bf5 100644
--- a/src/mesa/main/compiler.h
+++ b/src/mesa/main/compiler.h
@@ -252,6 +252,21 @@ static INLINE GLuint CPU_TO_LE32(GLuint x)
       (void) sizeof(char [1 - 2*!(COND)]); \
    } while (0)
 
+/**
+ * Unreachable macro. Useful for suppressing "control reaches end of non-void
+ * function" warnings.
+ */
+#if __GNUC__ >= 4 && __GNUC_MINOR__ >= 5
+#define unreachable __builtin_unreachable()
+#elif (defined(__clang__) && defined(__has_builtin))
+# if __has_builtin(__builtin_unreachable)
+#  define unreachable __builtin_unreachable()
+# endif
+#endif
+
+#ifndef unreachable
+#define unreachable
+#endif
 
 #if (__GNUC__ >= 3)
 #define PRINTFLIKE(f, a) __attribute__ ((format(__printf__, f, a)))
-- 
1.8.3.2