Hi, I'm working on a project that uses the Boost thread library. The code is pretty simple and creates one thread to a function. To test out the code I created, I create a console app and tested the code on 2 platforms: Mac OS X for Intel and Mac OS X for PowerPC. The code worked fine in the console app so I incorporated the code into my main project, which is a dylib. The code worked fine on the Intel Mac, but when I debugged the dylib on the PowerPC Mac, I get a EXC_BAD_ACCESS error. After spending many hours trying to find out what the cause of the problem is, the only thing I could derive was that the address that Boost was using to access my function was wrong. Before the error, I have the following address to my function: (gdb) print f $1 = (void (*)(void)) 0x33658e4 <MyWorkerThread()> When I get the EXC_BAD_ACCESS error, the debugger stops at the following line: On line 95 of file function_template.hpp struct BOOST_FUNCTION_VOID_FUNCTION_INVOKER { static BOOST_FUNCTION_VOID_RETURN_TYPE invoke(any_pointer function_ptr BOOST_FUNCTION_COMMA BOOST_FUNCTION_PARMS) { HERE--> FunctionPtr f = reinterpret_cast<FunctionPtr>(function_ptr.func_ptr); BOOST_FUNCTION_RETURN(f(BOOST_FUNCTION_ARGS)); } }; The address at this point is the following: (gdb) print f $2 = (void (*)(void)) 0xf0798dd0 I went over the code over and over again but I cannot figure out what is causing the original function address to be changed. Now for the question! How can I debug this better? The problem that I am finding is that my debugger jumps to different parts of the project, but I cannot pinpoint the actual code that is causing this problem. Any suggestions? Thanks in advance! -Jaime