Hi, I'm trying to compile graph-tool with parallel algorithms enabled, but I must be missing something from the instructions on: http://projects.forked.de/graph-tool/wiki/ParallelAlgorithms Basically, the problem is where it says: $ cd gcc-4.2.0 $ patch -E -p1 < ../gcc-shared-openmp.patch I don't have a folder gcc-4.2.0 on my Ubuntu 64 bit system, although I have gcc-4.2.0 installed. I've tried to save the patch to this directory instead: $cd /usr/lib/gcc/x86_64-linux-gnu/4.2 But when I issue the command I get: Patch: **** Only garbage was found in the patch input. Any help would be much appreciated :) Thanks, Rui