Hi, getting my feet wet with variadic templates, I switched on c++0x support in gcc. Unfortunately, I am experiencing a linker error for the following minimal program: ------------------ #define BOOST_FILESYSTEM_VERSION 3 #define BOOST_FILESYSTEM_NO_DEPRECATED #include <boost/filesystem.hpp> int main() { boost::filesystem::copy_file("a", "b"); } ------------------ rbock@rbock:~/temp/test$ g++ File.cpp -std=c++0x -I boost/1.44/include -L boost/1.44/lib -l boost_filesystem -l boost_system /tmp/ccwkcQpq.o: In function `boost::filesystem3::copy_file(boost::filesystem3::path const&, boost::filesystem3::path const&)': File.cpp:(.text._ZN5boost11filesystem39copy_fileERKNS0_4pathES3_[boost::filesystem3::copy_file(boost::filesystem3::path const&, boost::filesystem3::path const&)]+0x2a): undefined reference to `boost::filesystem3::detail::copy_file(boost::filesystem3::path const&, boost::filesystem3::path const&, boost::filesystem3::copy_option, boost::system::error_code*)' collect2: ld returned 1 exit status Experienced on Ubuntu-10.4, 64bit, gcc (Ubuntu 4.4.3-4ubuntu5) 4.4.3 Other boost libraries seem to work fine, other functions within Boost.Filesystem work fine, too. When I rebuild boost with -std=c++0x, then the linking problem is gone, but I experience crashes in the boost::thread constructor :-( Any ideas? Thanks and regards, Roland