diff --git a/test/Jamfile.v2 b/test/Jamfile.v2 index 55fdd44..07d771a 100644 --- a/test/Jamfile.v2 +++ b/test/Jamfile.v2 @@ -36,6 +36,7 @@ run string_view_test2.cpp ; run string_view_test_io.cpp ; run value_init_test.cpp ; +run value_init_test2.cpp ; run value_init_workaround_test.cpp ; run initialized_test.cpp ; compile-fail value_init_test_fail1.cpp ; diff --git a/test/value_init_test2.cpp b/test/value_init_test2.cpp new file mode 100644 index 0000000..e3438cc --- /dev/null +++ b/test/value_init_test2.cpp @@ -0,0 +1,169 @@ +// Copyright 2010, Niels Dekker. +// +// Distributed under the Boost Software License, Version 1.0. (See +// accompanying file LICENSE_1_0.txt or copy at +// http://www.boost.org/LICENSE_1_0.txt) +// +// Test program for the boost::value_initialized workaround. +// +// 17 June 2010 (Created) Niels Dekker + +#include +#include +#include +#include + +namespace +{ + struct empty_struct + { + }; + + // A POD aggregate struct derived from an empty struct. + // Similar to struct Foo1 from Microsoft Visual C++ bug report 484295, + // "VC++ does not value-initialize members of derived classes without + // user-declared constructor", reported in 2009 by Sylvester Hesp: + // https://connect.microsoft.com/VisualStudio/feedback/details/484295 + struct derived_struct: empty_struct + { + int data; + }; + + bool is_value_initialized(const derived_struct& arg) + { + return arg.data == 0; + } + + + class virtual_destructor_holder + { + public: + int i; + virtual ~virtual_destructor_holder() + { + } + }; + + bool is_value_initialized(const virtual_destructor_holder& arg) + { + return arg.i == 0; + } + + // Equivalent to the Stats class from GCC Bug 33916, + // "Default constructor fails to initialize array members", reported in 2007 by + // Michael Elizabeth Chastain: http://gcc.gnu.org/bugzilla/show_bug.cgi?id=33916 + // and fixed for GCC 4.2.4. + class private_int_array_pair + { + friend bool is_value_initialized(const private_int_array_pair& arg); + private: + int first[12]; + int second[12]; + }; + + bool is_value_initialized(const private_int_array_pair& arg) + { + for ( unsigned i = 0; i < 12; ++i) + { + if ( (arg.first[i] != 0) || (arg.second[i] != 0) ) + { + return false; + } + } + return true; + } + + struct int_pair_struct + { + int first; + int second; + }; + + typedef int int_pair_struct::*ptr_to_member_type; + + struct ptr_to_member_struct + { + ptr_to_member_type data; + }; + + bool is_value_initialized(const ptr_to_member_struct& arg) + { + return arg.data == 0; + } + + template + bool is_value_initialized(const T(& arg)[2]) + { + return + is_value_initialized(arg[0]) && + is_value_initialized(arg[1]); + } + + template + bool is_value_initialized(const boost::value_initialized& arg) + { + return is_value_initialized(arg.data()); + } + + // Returns zero when the specified object is value-initializated, and one otherwise. + // Prints a message to standard output if the value-initialization has failed. + template + unsigned failed_to_value_initialized(const T& object, const char *const object_name) + { + if ( is_value_initialized(object) ) + { + return 0u; + } + else + { + std::cout << "Note: Failed to value-initialize " << object_name << '.' << std::endl; + return 1u; + } + } + +// A macro that passed both the name and the value of the specified object to +// the function above here. +#define FAILED_TO_VALUE_INITIALIZE(value) failed_to_value_initialized(value, #value) + + // Equivalent to the dirty_stack() function from GCC Bug 33916, + // "Default constructor fails to initialize array members", reported in 2007 by + // Michael Elizabeth Chastain: http://gcc.gnu.org/bugzilla/show_bug.cgi?id=33916 + void dirty_stack() + { + unsigned char array_on_stack[4096]; + for (unsigned i = 0; i < sizeof(array_on_stack); ++i) + { + array_on_stack[i] = 0x11; + } + } + +} + + +int main() +{ +#ifdef BOOST_DETAIL_VALUE_INIT_WORKAROUND_SUGGESTED + + std::cout << "BOOST_DETAIL_VALUE_INIT_WORKAROUND_SUGGESTED is defined.\n\n"; + +#endif + + dirty_stack(); + + BOOST_TEST( is_value_initialized( boost::value_initialized() ) ); + BOOST_TEST( is_value_initialized( boost::value_initialized() ) ); + BOOST_TEST( is_value_initialized( boost::value_initialized() ) ); + +#if !BOOST_WORKAROUND( BOOST_MSVC, BOOST_TESTED_AT(1925) ) + + // Null pointers to data members are represented as -1 in MSVC, but + // value initialization sets them to all zero. The workaround employed + // by value_initialized<> is to memset the storage to all zero, which + // doesn't help. + + BOOST_TEST( is_value_initialized( boost::value_initialized() ) ); + +#endif + + return boost::report_errors(); +}