How do I apply a patch for a fix that has not made it to a release?

edit

Following these instructions http://www.ros.org/wiki/electric/Installation/OSX/Homebrew and executing

rosinstall ~/ros "http://packages.ros.org/cgi-bin/gen_rosinstall.py?rosdistro=electric&variant=desktop-full&overlay=no"

I get the following:

/ros/ros_comm/tools/rosconsole/src/rosconsole/rosconsole.cpp:33:2: error: #error This code is known to provoke a compiler crash with llvm-gcc 4.2. You will have better luck with clang++. See code.ros.org/trac/ros/ticket/3626
  /Users/jwoods/ros/ros_comm/tools/rosconsole/src/rosconsole/rosconsole.cpp:745: internal compiler error: Segmentation fault
  Please submit a full bug report,
  with preprocessed source if appropriate.
  See <URL:http://developer.apple.com/bugreporter> for instructions.
  make[3]: *** [CMakeFiles/rosconsole.dir/src/rosconsole/rosconsole.o] Error 1
  make[2]: *** [CMakeFiles/rosconsole.dir/all] Error 2
  make[1]: *** [all] Error 2

I have tried manually making the change to CMakeLists.txt as is present in the patch, but this is overwritten the next time I try to run the rosinstall.

What is the process for applying a patch so that it isn't overwritten?

Thanks!