Try this:
cd ~/ffmpeg_sources hg clone https:///multicoreware/x265 cd ~/ffmpeg_sources/x265/build/linux PATH="$HOME/bin:$PATH" cmake -G "Unix Makefiles" -DCMAKE_INSTALL_PREFIX="$HOME/ffmpeg_build" -DENABLE_SHARED:bool=off ../../source make make install
Then, for ffmpeg itself (assuming you have all the other libs installed according to the guide):
cd ~/ffmpeg_sources/ffmpeg PATH="$HOME/bin:$PATH" PKG_CONFIG_PATH="$HOME/ffmpeg_build/lib/pkgconfig" ./configure --prefix="$HOME/ffmpeg_build" --extra-cflags="-I$HOME/ffmpeg_build/include" --extra-ldflags="-L$HOME/ffmpeg_build/lib" --bindir="$HOME/bin" --pkg-config-flags="--static" --enable-gpl --enable-libass --enable-libfdk-aac --enable-libfreetype --enable-libmp3lame --enable-libopus --enable-libtheora --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libx265 --enable-nonfree
Then
PATH="$HOME/bin:$PATH" make make install
Worked for me on Linux Mint 17. Say thank you to Lou from FFmpeg for figuring this out.
The -DENABLE_SHARED:bool=off
part in particular is something that may be useful to mention on the x265 wiki.