Use C++ static_assert from N3928 when available

1 files changed, 19 insertions, 12 deletions

diff --git a/misc.h b/misc.h
index c405c4ab..23093be3 100644
--- a/misc.h
+++ b/misc.h
@@ -142,8 +142,13 @@ class Integer;
 #if CRYPTOPP_DOXYGEN_PROCESSING

 /// \brief Compile time assertion

 /// \param expr the expression to evaluate

-/// \details Asserts the expression expr though a dummy struct.

-#define CRYPTOPP_COMPILE_ASSERT(expr) { ... }

+/// \details Asserts the expression <tt>expr</tt> during compile. If C++14 and

+///  N3928 are available, then C++14 <tt>static_assert</tt> is used. Otherwise,

+///  a <tt>CompileAssert</tt> structure is used. When the structure is used

+///  a negative-sized array triggers the assert at compile time.

+# define CRYPTOPP_COMPILE_ASSERT(expr) { ... }

+#elif defined(CRYPTOPP_CXX11_STATIC_ASSERT)

+# define CRYPTOPP_COMPILE_ASSERT(expr) static_assert(expr)

 #else // CRYPTOPP_DOXYGEN_PROCESSING

 template <bool b>

 struct CompileAssert

@@ -151,22 +156,24 @@ struct CompileAssert
 	static char dummy[2*b-1];

 };

 

-#define CRYPTOPP_COMPILE_ASSERT(assertion) CRYPTOPP_COMPILE_ASSERT_INSTANCE(assertion, __LINE__)

+#define CRYPTOPP_COMPILE_ASSERT(assertion) \

+    CRYPTOPP_COMPILE_ASSERT_INSTANCE(assertion, (__LINE__-1))

+#define CRYPTOPP_ASSERT_JOIN(X, Y) CRYPTOPP_DO_ASSERT_JOIN(X, Y)

+#define CRYPTOPP_DO_ASSERT_JOIN(X, Y) X##Y

+

 #if defined(CRYPTOPP_EXPORTS) || defined(CRYPTOPP_IMPORTS)

-#define CRYPTOPP_COMPILE_ASSERT_INSTANCE(assertion, instance)

+# define CRYPTOPP_COMPILE_ASSERT_INSTANCE(assertion, instance)

 #else

-# if defined(__GNUC__)

+# if defined(__GNUC__) || defined(__clang__)

 #  define CRYPTOPP_COMPILE_ASSERT_INSTANCE(assertion, instance) \

-		static CompileAssert<(assertion)> \

-		CRYPTOPP_ASSERT_JOIN(cryptopp_CRYPTOPP_ASSERT_, instance) __attribute__ ((unused))

+       static CompileAssert<(assertion)> \

+       CRYPTOPP_ASSERT_JOIN(cryptopp_CRYPTOPP_ASSERT_, instance) __attribute__ ((unused))

 # else

 #  define CRYPTOPP_COMPILE_ASSERT_INSTANCE(assertion, instance) \

-		static CompileAssert<(assertion)> \

-		CRYPTOPP_ASSERT_JOIN(cryptopp_CRYPTOPP_ASSERT_, instance)

-# endif // __GNUC__

+       static CompileAssert<(assertion)> \

+       CRYPTOPP_ASSERT_JOIN(cryptopp_CRYPTOPP_ASSERT_, instance)

+# endif // GCC or Clang

 #endif

-#define CRYPTOPP_ASSERT_JOIN(X, Y) CRYPTOPP_DO_ASSERT_JOIN(X, Y)

-#define CRYPTOPP_DO_ASSERT_JOIN(X, Y) X##Y

 

 #endif // CRYPTOPP_DOXYGEN_PROCESSING