Hi all, I had a problem with boost 1.33.1, building it on windows XP inside the msys (MinGW) environment. The link step generates this command: "g++" "-Wl,--enable-auto-image-base" "-Wl,--exclude-symbols,_bss_end__:_bss_start__:_data_end__:_data_start__" "-Wl,--out-implib,..\..\..\bin\boost\libs\signals\build\boost_signals.dll\mingw\debug\boost_signals-mgw-d-1_33_1.lib" -g -shared -Wl,--allow-multiple-definition -mno-cygwin -o "..\..\..\bin\boost\libs\signals\build\boost_signals.dll\mingw\debug\boost_signals-mgw-d-1_33_1.dll" -L"" "..\..\..\bin\boost\libs\signals\build\boost_signals.dll\mingw\debug\trackable.obj" "..\..\..\bin\boost\libs\signals\build\boost_signals.dll\mingw\debug\connection.obj" "..\..\..\bin\boost\libs\signals\build\boost_signals.dll\mingw\debug\named_slot_map.obj" "..\..\..\bin\boost\libs\signals\build\boost_signals.dll\mingw\debug\signal_base.obj" "..\..\..\bin\boost\libs\signals\build\boost_signals.dll\mingw\debug\slot.obj" and it fails, giving a message about not being able to find a symbol for a method in trackable. I edited tools/build/v1/mingw-tools.jam and added this line: flags mingw STDLIBPATH : $(GCC_BIN_DIRECTORY) ; + flags mingw LIBPATH : $(GCC_BIN_DIRECTORY) ; } And tried again. This time it worked, with the following command: "g++" "-Wl,--enable-auto-image-base" "-Wl,--exclude-symbols,_bss_end__:_bss_start__:_data_end__:_data_start__" "-Wl,--out-implib,..\..\..\bin\boost\libs\signals\build\boost_signals.dll\mingw\release\boost_signals-mgw-1_33_1.lib" -s -shared -Wl,--allow-multiple-definition -mno-cygwin -o "..\..\..\bin\boost\libs\signals\build\boost_signals.dll\mingw\release\boost_signals-mgw-1_33_1.dll" -L"" -L"" "..\..\..\bin\boost\libs\signals\build\boost_signals.dll\mingw\release\trackable.obj" "..\..\..\bin\boost\libs\signals\build\boost_signals.dll\mingw\release\connection.obj" "..\..\..\bin\boost\libs\signals\build\boost_signals.dll\mingw\release\named_slot_map.obj" "..\..\..\bin\boost\libs\signals\build\boost_signals.dll\mingw\release\signal_base.obj" "..\..\..\bin\boost\libs\signals\build\boost_signals.dll\mingw\release\slot.obj" The difference is that there is an EXTRA -L"" in the command. I suspect that having any -L"" is a bad idea, and if there is no parameter, it should be omitted all together. I bet this command works ONLY because, to g++, it looks like g++ blah blah -L"-L" ie the second -L becomes the parameter for the first -L (spaces are allowed after the -L flag). I dont understand bjam's Jamfiles well enough to fix this properly. Can someone help put together a patch for this? Thanks Paul