https://svn.boost.org/trac10/ticket/9739 <p> If the following file is compiled with g++ or clang++ <em>without</em> using the "-ftrapv" flag, it runs fine, irrespective of which lines are commented out. </p> <p> If we compile <em>with</em> "-ftrapv", with either of the <em>causes crash</em> lines uncommented, then the program will crash on start-up, before even entering the "main" function. (The crashy code lives in a function which is never called.) </p> <p> This is true of both g++ and clang++. </p> <p> I am using Boost 1.55, g++ 4.8.1, clang 3.2, on Mint GNU/Linux, x86-64. </p> <p> The -ftrapv flag ( described in gcc.gnu.org/onlinedocs/gcc-4.8.1/gcc/Code-Gen-Options.html#index-ftrapv-2326 (spam-detection forced me to sabotage the link) ) <em>generates traps for signed overflow on addition, subtraction, multiplication operations</em>. </p> <pre class="wiki">#include &lt;boost/multiprecision/cpp_dec_float.hpp&gt; #include &lt;boost/version.hpp&gt; #if ( BOOST_VERSION != 105500 ) #error Boost 1.55 please #endif void neverCalled() { //boost::multiprecision::cpp_dec_float_100 e; // ok //boost::multiprecision::cpp_dec_float_100 f = 42; // ok //boost::multiprecision::cpp_dec_float_100 g = 42.0f; // causes crash if -ftrapv is used boost::multiprecision::cpp_dec_float_100 h = 42.0; // causes crash if -ftrapv is used } int main() { return 0; } </pre> en-us /htdocs/site/boost.png https://svn.boost.org/trac10/ticket/9739 Trac 1.4.3 MaxBarraclough Wed, 05 Mar 2014 12:37:29 GMT https://svn.boost.org/trac10/ticket/9739#comment:2 https://svn.boost.org/trac10/ticket/9739#comment:2 <ul> <li><strong>status</strong> <span class="trac-field-old">new</span> → <span class="trac-field-new">closed</span> </li> <li><strong>resolution</strong> → <span class="trac-field-new">duplicate</span> </li> </ul> <p> Closing as a duplicate. </p> Ticket