id summary reporter owner description type status milestone component version severity resolution keywords cc 11426 Warning C4996 at using std::fill_n Yury Podpruzhnikov No-Maintainer "== Problem == We develop project using '''msvc 2013'''. Warning appear just after include During compilation '''debug''' version with default settings. After compilation I take warning: {{{ 1>C:\Program Files (x86)\Microsoft Visual Studio 12.0\VC\include\xutility(2715): warning C4996: 'std::_Fill_n': Function call with parameters that may be unsafe - this call relies on the caller to check that the passed values are correct. To disable this warning, use -D_SCL_SECURE_NO_WARNINGS. See documentation on how to use Visual C++ 'Checked Iterators' 1> C:\Program Files (x86)\Microsoft Visual Studio 12.0\VC\include\xutility(2701) : see declaration of 'std::_Fill_n' 1> X:\xxx\boost_1_58_0\boost/random/detail/polynomial.hpp(126) : see reference to function template instantiation '_OutIt std::fill_n(_OutIt,_Diff,const _Ty &)' being compiled 1> with 1> [ 1> _OutIt=boost::random::detail::polynomial_ops::digit_t * 1> , _Diff=size_t 1> , _Ty=boost::random::detail::polynomial_ops::digit_t 1> ] }}} problem source code is: {{{ static void multiply(const digit_t * lhs, std::size_t lhs_size, const digit_t * rhs, std::size_t rhs_size, digit_t * output) { std::fill_n(SilenceMSVC_C4996(output), lhs_size + rhs_size, digit_t(0)); // <<<<<< problem line multiply_add(lhs, lhs_size, rhs, rhs_size, output); } }}} == Cause == Warning appear because '''Visual C++ Checked Iterators''' is enabled. See [https://msdn.microsoft.com/en-us/library/vstudio/aa985965%28v=vs.120%29.aspx]. This tecnology don't allow use pointer with std::fill_n (and others). And so we take warning. == Disable warning don't work! == Try disable warning. {{{ // some std library #include #include #pragma warning(disable:4996) #include }}} Warning is still exist. As I understand. MSVC think what warning appear in xutility (not in polynomial.hpp). Because if add #pragma at start of the program then warning will be disabled. But disable this warning in xutility is wrong. == Decision == There is one case is described at MS article [https://msdn.microsoft.com/en-us/library/vstudio/aa985965%28v=vs.120%29.aspx] - using '''stdext::make_checked_array_iterator'''. {{{ // WARNING C4996: Pointers cannot be checked in debug mode // (an overrun will trigger undefined behavior) int a6[16]; int * p6 = a6; transform(v.begin(), v.end(), p6, [](int n) { return n * 6; }); print(""a6: "", a6); // OK: stdext::checked_array_iterator is checked in debug mode // (an overrun will trigger a debug assertion) int a7[16]; int * p7 = a7; transform(v.begin(), v.end(), stdext::make_checked_array_iterator(p7, 16), [](int n) { return n * 7; }); print(""a7: "", a7); }}} I wrote decision: {{{ // Silence using pointer in std::find and others. >= Visual Studio 2013, debug. #ifndef SilenceMSVC_C4996 #if BOOST_WORKAROUND(BOOST_MSVC, >= 1800) && _ITERATOR_DEBUG_LEVEL != 0 #define SilenceMSVC_C4996(pointer) stdext::make_unchecked_array_iterator(pointer) #else #define SilenceMSVC_C4996(pointer) pointer #endif #endif }}} And replace calling std::fill_n with next code: {{{ std::fill_n(SilenceMSVC_C4996(output), lhs_size + rhs_size, digit_t(0)); }}} == Other warning places == I also used this macros in:[[BR]] ''boost\random\detail\polynomial.hpp'':[[BR]] static void mod_pow_x(boost::uintmax_t exponent, const digit_t * mod, std::size_t mod_bits, digit_t * out) replace (2 times): {{{ std::fill_n(out + 1, n - 1, digit_t(0)); }}} to {{{ std::fill_n(SilenceMSVC_C4996(out + 1), n - 1, digit_t(0)); }}} In ''boost/algorithm/string/detail/classification.hpp'':[[BR]] replace: {{{ ::std::copy(::boost::begin(Range), ::boost::end(Range), Storage); }}} to {{{ ::std::copy(::boost::begin(Range), ::boost::end(Range), SilenceMSVC_C4996(Storage));}}} }}} " Bugs closed To Be Determined random Boost 1.58.0 Problem wontfix