Matthias Schabel wrote:
hmmm...decided to try and test this guy out and based on the docs I would think the following code would compile, but it doesn't in VC++ 8.0...g++ gobbles it up ok though.
A better fix is to replace the code between the #ifdef MCS_HAS_TYPEOF ... #endif // MCS_HAS_TYPEOF with the following:
Ok, I probably won't get to do this until Friday again...that's the day I get to work on personal things at work for a few hours...I don't have VC. I was profiling my own version and it was dog slow compared to doubles. I wanted to check yours. I did here at home with g++ on Linux and our two versions compare equally wrt the static dim quantity. I had to really vamp up the optimizations of course to get them as fast as doubles (I couldn't find the right options for VC) and I still can't do as deep a recursion level without a seg fault...this is actually by quite a margin...several orders of magnitude. Both versions fail at the same point. Here is test code...add a 0 to the end of tlim and I get a crash on the quantity version: #include <boost/units/io.hpp> #include <boost/units/systems/si_units.hpp> int const tlim = 50000; double f_dbl(double x, double y, double z, int count) { static double const C = 3.14; if (!count) return 0; return ((x + y) * z * C) + f_dbl(x, y, z, count - 1); } using namespace boost::units; using namespace boost::units::SI; quantity<volume> f_qty(quantity<length> x, quantity<length> y, quantity<length> z, int count) { static quantity<length> const C = 3.14 * meters; if (!count) return 0 * cubic_meters; return ((x + y) * z * C) + f_qty(x, y, z, count - 1); } #include <iostream> int main() { std::cout << f_dbl(1,2,3,tlim) << std::endl; std::cout << f_qty(1 * meters, 2 * meters, 3 * meters, tlim) << std::endl; } COMMAND LINE: nroberts@localhost ~/projects/prof_units $ g++ -I/home/nroberts/units -pg -O3 prof_mcs.cpp This is likely implementation dependant and maybe there's still more ops.