1 //  (C) Copyright John Maddock 2000.

     2 //  Use, modification and distribution are subject to the 

     3 //  Boost Software License, Version 1.0. (See accompanying file 

     4 //  LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)

     5 

     6 //  See http://www.boost.org/libs/static_assert for documentation.

     7 

     8 /*

     9  Revision history:

    10    02 August 2000

    11       Initial version.

    12 */

    13 

    14 #ifndef BOOST_STATIC_ASSERT_HPP

    15 #define BOOST_STATIC_ASSERT_HPP

    16 

    17 #include <boost/config.hpp>

    18 #include <boost/detail/workaround.hpp>

    19 

    20 #ifdef __BORLANDC__

    21 //

    22 // workaround for buggy integral-constant expression support:

    23 #define BOOST_BUGGY_INTEGRAL_CONSTANT_EXPRESSIONS

    24 #endif

    25 

    26 #if defined(__GNUC__) && (__GNUC__ == 3) && ((__GNUC_MINOR__ == 3) || (__GNUC_MINOR__ == 4))

    27 // gcc 3.3 and 3.4 don't produce good error messages with the default version:

    28 #  define BOOST_SA_GCC_WORKAROUND

    29 #endif

    30 

    31 //

    32 // If the compiler issues warnings about old C style casts,

    33 // then enable this:

    34 //

    35 #if defined(__GNUC__) && ((__GNUC__ > 3) || ((__GNUC__ == 3) && (__GNUC_MINOR__ >= 4)))

    36 #  define BOOST_STATIC_ASSERT_BOOL_CAST( x ) ((x) == 0 ? false : true)

    37 #else

    38 #  define BOOST_STATIC_ASSERT_BOOL_CAST(x) (bool)(x)

    39 #endif

    40 

    41 #ifdef BOOST_HAS_STATIC_ASSERT

    42 #  define BOOST_STATIC_ASSERT( B ) static_assert(B, #B)

    43 #else

    44 

    45 namespace boost{

    46 

    47 // HP aCC cannot deal with missing names for template value parameters

    48 template <bool x> struct STATIC_ASSERTION_FAILURE;

    49 

    50 template <> struct STATIC_ASSERTION_FAILURE<true> { enum { value = 1 }; };

    51 

    52 // HP aCC cannot deal with missing names for template value parameters

    53 template<int x> struct static_assert_test{};

    54 

    55 }

    56 

    57 //

    58 // Implicit instantiation requires that all member declarations be

    59 // instantiated, but that the definitions are *not* instantiated.

    60 //

    61 // It's not particularly clear how this applies to enum's or typedefs;

    62 // both are described as declarations [7.1.3] and [7.2] in the standard,

    63 // however some compilers use "delayed evaluation" of one or more of

    64 // these when implicitly instantiating templates.  We use typedef declarations

    65 // by default, but try defining BOOST_USE_ENUM_STATIC_ASSERT if the enum

    66 // version gets better results from your compiler...

    67 //

    68 // Implementation:

    69 // Both of these versions rely on sizeof(incomplete_type) generating an error

    70 // message containing the name of the incomplete type.  We use

    71 // "STATIC_ASSERTION_FAILURE" as the type name here to generate

    72 // an eye catching error message.  The result of the sizeof expression is either

    73 // used as an enum initialiser, or as a template argument depending which version

    74 // is in use...

    75 // Note that the argument to the assert is explicitly cast to bool using old-

    76 // style casts: too many compilers currently have problems with static_cast

    77 // when used inside integral constant expressions.

    78 //

    79 #if !defined(BOOST_BUGGY_INTEGRAL_CONSTANT_EXPRESSIONS)

    80 

    81 #if defined(BOOST_MSVC) && (BOOST_MSVC < 1300)

    82 // __LINE__ macro broken when -ZI is used see Q199057

    83 // fortunately MSVC ignores duplicate typedef's.

    84 #define BOOST_STATIC_ASSERT( B ) \

    85    typedef ::boost::static_assert_test<\

    86       sizeof(::boost::STATIC_ASSERTION_FAILURE< (bool)( B ) >)\

    87       > boost_static_assert_typedef_

    88 #elif defined(BOOST_MSVC)

    89 #define BOOST_STATIC_ASSERT( B ) \

    90    typedef ::boost::static_assert_test<\

    91       sizeof(::boost::STATIC_ASSERTION_FAILURE< BOOST_STATIC_ASSERT_BOOL_CAST ( B ) >)>\

    92          BOOST_JOIN(boost_static_assert_typedef_, __COUNTER__)

    93 #elif defined(BOOST_INTEL_CXX_VERSION) || defined(BOOST_SA_GCC_WORKAROUND)

    94 // agurt 15/sep/02: a special care is needed to force Intel C++ issue an error 

    95 // instead of warning in case of failure

    96 # define BOOST_STATIC_ASSERT( B ) \

    97     typedef char BOOST_JOIN(boost_static_assert_typedef_, __LINE__) \

    98         [ ::boost::STATIC_ASSERTION_FAILURE< BOOST_STATIC_ASSERT_BOOL_CAST( B ) >::value ]

    99 #elif defined(__sgi)

   100 // special version for SGI MIPSpro compiler

   101 #define BOOST_STATIC_ASSERT( B ) \

   102    BOOST_STATIC_CONSTANT(bool, \

   103      BOOST_JOIN(boost_static_assert_test_, __LINE__) = ( B )); \

   104    typedef ::boost::static_assert_test<\

   105      sizeof(::boost::STATIC_ASSERTION_FAILURE< \

   106        BOOST_JOIN(boost_static_assert_test_, __LINE__) >)>\

   107          BOOST_JOIN(boost_static_assert_typedef_, __LINE__)

   108 #elif BOOST_WORKAROUND(__MWERKS__, <= 0x3003)

   109 // special version for CodeWarrior <= 8.x

   110 #define BOOST_STATIC_ASSERT( B ) \

   111    BOOST_STATIC_CONSTANT(int, \

   112      BOOST_JOIN(boost_static_assert_test_, __LINE__) = \

   113        sizeof(::boost::STATIC_ASSERTION_FAILURE< BOOST_STATIC_ASSERT_BOOL_CAST( B ) >) )

   114 #else

   115 // generic version

   116 #define BOOST_STATIC_ASSERT( B ) \

   117    typedef ::boost::static_assert_test<\

   118       sizeof(::boost::STATIC_ASSERTION_FAILURE< BOOST_STATIC_ASSERT_BOOL_CAST( B ) >)>\

   119          BOOST_JOIN(boost_static_assert_typedef_, __LINE__)

   120 #endif

   121 

   122 #else

   123 // alternative enum based implementation:

   124 #define BOOST_STATIC_ASSERT( B ) \

   125    enum { BOOST_JOIN(boost_static_assert_enum_, __LINE__) \

   126       = sizeof(::boost::STATIC_ASSERTION_FAILURE< (bool)( B ) >) }

   127 #endif

   128 #endif // ndef BOOST_HAS_STATIC_ASSERT

   129 

   130 #endif // BOOST_STATIC_ASSERT_HPP

   131 

   132