http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54059
Bug #: 54059 Summary: g++ silently omits code that creates a std::chrono::millisecond temporary Classification: Unclassified Product: gcc Version: unknown Status: UNCONFIRMED Severity: normal Priority: P3 Component: c++ AssignedTo: unassig...@gcc.gnu.org ReportedBy: ja...@cornsyrup.org jason@ps027 ~/bug$ g++-4.7 -std=c++11 bug.cc jason@ps027 ~/bug$ ./a.out got 100 jason@ps027 ~/bug$ cat bug.cc #include <chrono> #include <iostream> struct foo { foo(std::chrono::milliseconds ms) { std::cout << "got " << ms.count() << "\n"; } }; int main() { foo f1(std::chrono::milliseconds(100)); unsigned int a = 200; foo f2(std::chrono::milliseconds(a)); return 0; } jason@ps027 ~/bug$ g++-4.7 -v Using built-in specs. COLLECT_GCC=g++-4.7 COLLECT_LTO_WRAPPER=/usr/lib/gcc/x86_64-linux-gnu/4.7/lto-wrapper Target: x86_64-linux-gnu Configured with: ../src/configure -v --with-pkgversion='Ubuntu/Linaro 4.7.1-4+ub1' --with-bugurl=file:///usr/share/doc/gcc-4.7/README.Bugs --enable-languages=c,c++,go,fortran,objc,obj-c++ --prefix=/usr --program-suffix=-4.7 --enable-shared --enable-linker-build-id --with-system-zlib --libexecdir=/usr/lib --without-included-gettext --enable-threads=posix --with-gxx-include-dir=/usr/include/c++/4.7 --libdir=/usr/lib --enable-nls --enable-clocale=gnu --enable-libstdcxx-debug --enable-libstdcxx-time=yes --enable-gnu-unique-object --enable-plugin --enable-objc-gc --disable-werror --with-arch-32=i586 --with-tune=generic --enable-checking=release --build=x86_64-linux-gnu --host=x86_64-linux-gnu --target=x86_64-linux-gnu Thread model: posix gcc version 4.7.1 (Ubuntu/Linaro 4.7.1-4+ub1)