Do you develop in XCode ? I remember that while developing on XCode there is an option that does fast linking (it is called Zero Link) and if you check that, it does not really link your application at link time but only at run time. So I think this is in fact a linking problem, disable the Zero Link option under XCode and your code will probably fail to link. As to why it does not link, I do not know, which library (boost) are you trying to link to ? Jean-Noël _____ De : boost-users-bounces@lists.boost.org [mailto:boost-users-bounces@lists.boost.org] De la part de Locatelli Jérôme Envoyé : jeudi 9 février 2006 14:14 À : boost-users@lists.boost.org Objet : [Boost-users] pd darwin Symbol not found I'am writing a application on MacOS 10.4.4 using darwin 8 with gcc 4, I compile and link my application without problem but when I run my application , I've got the error bellow. Has anybody got an idear?? Thanks. dyld: lazy symbol binding failed: Symbol not found: __ZN5boost6detail3tss4initEPNS_9function1IvPvSaINS_13function_baseEEEE Referenced from: /Users/locatelli/Projets/ics/IcsServer/obj.ics/../lib/libIcsServerCommandSystem.0 Expected in: flat namespace dyld: Symbol not found: __ZN5boost6detail3tss4initEPNS_9function1IvPvSaINS_13function_baseEEEE Referenced from: /Users/locatelli/Projets/ics/IcsServer/obj.ics/../lib/libIcsServerCommandSystem.0 Expected in: flat namespace Trace/BPT trap --------------------------------------------------- Locatelli Jérôme Institut Laue-Langevin Service Contrôle des instruments 6 rue Jules Horowitz, BP 156 38042 Grenoble cedex 9 http://www.ill.fr/ Tel: 33 (0)4 76 20 76 27 Fax: 33 (0)4 76 20 77 00 ---------------------------------------------------