Use C++11 static_assert() if available.

src/checks.h

Index: src/checks.h
diff --git a/src/checks.h b/src/checks.h
index d0a0c2b5acf5da52e3f2c49d3138b62904fa34df..55dc1bc7024c79fb02b9aea9b23e6cfb996c7e2c 100644
--- a/src/checks.h
+++ b/src/checks.h
@@ -230,6 +230,13 @@ inline void CheckNonEqualsHelper(const char* file,
 #define CHECK_LE(a, b) CHECK((a) <= (b))
 
 
+// Use C++11 static_assert if possible, which gives error
+// messages that are easier to understand on first sight.
+#if __cplusplus >= 201103L || \
+    (defined(__has_feature) && __has_feature(cxx_static_assert)) || \
+    (defined(__has_extension) && __has_extension(cxx_static_assert))

[Sven Panne, 2013/07/18 06:45:30]

autoconf by hand? ;-)

+#define STATIC_CHECK(test) static_assert(test, #test)
+#else
 // This is inspired by the static assertion facility in boost.  This
 // is pretty magical.  If it causes you trouble on a platform you may
 // find a fix in the boost code.
@@ -249,6 +256,7 @@ template <int> class StaticAssertionHelper { };
   typedef                                                                     \
     StaticAssertionHelper<sizeof(StaticAssertion<static_cast<bool>((test))>)> \
     SEMI_STATIC_JOIN(__StaticAssertTypedef__, __LINE__)
+#endif
 
 
 extern bool FLAG_enable_slow_asserts;