Hi, First, I'm not sure if this is the right place to send patch to the build_extensions which live in the sandbox, I'm continuing to have complete build of Boost.GIL tests on Linux with 3rd-party dependencies configured using the build_extensions. It's trial and error process during which I've applied number of updates to .jam scripts for raster support libraries. The patch summary: zlib: added/removed .c source files jpeg: added/removed .c source files libtiff: - added missing tif_unix.c for <target-os>linux (not sure why <target-os>unix: could not kick in) - configure #define integral types required by tiffiop.h - added tiffxx target with C++ wrapper library (tif_stream.cxx) I have successfully used the extensions with the following libraries: jpeg-8a libpng-1.4.1 tiff-3.9.2 zlib-1.2.4 with GCC 4.4.5 on Linux 64-bit. I'm quite sure some of the changes could be mastered in much better way, but I lack of Boost.Build zen. Best regards, -- Mateusz Loskot, http://mateusz.loskot.net Charter Member of OSGeo, http://osgeo.org Member of ACCU, http://accu.org