You want to use the LLVM Gold linker plugin but LLVMgold.so can’t be found.
You should compile and install the LLVM gold plugin by yourself.
This guide has been tested on Ubuntu 12.04 and Ubuntu 12.10, but it should work on most Linux-based systems provided that you replace the package-manager-specific commands appropriately.
A more unspecific and overcomplex, but official guide can be found here.
First, install the Gold linker (replacement for GNU
ld) and the binutils dev package.
sudo apt-get install binutils-gold binutils-dev
After that, download the LLVM sourcecode from the LLVM releases website. Alternatively, get the latest version from SVN.
Unpack it and configure & compile it using these commands:
./configure --with-binutils-include=/usr/include make -j8 ENABLE_OPTIMIZED=1
After that, you can find
sudo cp ./Release+Asserts/lib/LLVMgold.so /usr/local/lib/
to put it in the directory where
clang/clang++ tries to find it.