Finaly I solved it. It was a STUPID mistake. I defined the BOOST_ROOT (.bashrc) and I thought it was enough. I was wrong and gcc was "using" the headers from boost 1.48 and trying to link with the libs I've compiled, boost 1.51. I just added�<i>-I/Data/Temp/Incoming/boost_1_51_0 </i>and it works. My original idea was using same headers with different possible libraries (Debug/Release)...<div> <br></div><div>Sorry for taking your time with a stupid "problem" like that one. Anyway, thank you for your time and help.</div><div><i><br></i></div><div>Regards,</div><div><i>--</i></div><div><i>Daniel�</i></div> <div><br><br><div class="gmail_quote">On 7 October 2012 19:26, Vicente J. Botet Escriba <span dir="ltr"><<a href="mailto:vicente.botet@wanadoo.fr" target="_blank">vicente.botet@wanadoo.fr</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"> Le 07/10/12 17:17, Daniel Santos a �crit :<div class="im"><br> <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"> Hi Vicente,<br> <br> Here it is:<br> $ g++ -o timer_5 -L/Data/Temp/Incoming/boost_1_<u></u>51_0/stage/lib -lpthread -lboost_system -lboost_thread timer_5.cpp<br> $ /tmp/ccClVUZf.o: In function `main':<br> $ timer_5.cpp:(.text+0xb3): undefined reference to `boost::thread::~thread()'<br> $ timer_5.cpp:(.text+0xe1): undefined reference to `boost::thread::~thread()'<br> $ collect2: error: ld returned 1 exit status<br> <br> <br> </blockquote></div> I don't see any -I <boost.1.51-folder>. From where are you getting the Boost header files?<br> Could you post the example?<div class="HOEnZb"><div class="h5"><br> <br> best,<br> Vicente<br> ______________________________<u></u>_________________<br> Boost-users mailing list<br> <a href="mailto:Boost-users@lists.boost.org" target="_blank">Boost-users@lists.boost.org</a><br> <a href="http://lists.boost.org/mailman/listinfo.cgi/boost-users" target="_blank">http://lists.boost.org/<u></u>mailman/listinfo.cgi/boost-<u></u>users</a><br> </div></div></blockquote></div><br></div>