Mac OS X R error "ld: warning: directory not found for option"

I am trying to install an R package from source, but getting an error:

* installing *source* package ‘mclust’ ...
** package ‘mclust’ successfully unpacked and MD5 sums checked
** libs
gfortran-4.8   -fPIC  -g -O2  -c mclust.f -o mclust.o
gfortran-4.8   -fPIC  -g -O2  -c mclustaddson.f -o mclustaddson.o
clang -dynamiclib -Wl,-headerpad_max_install_names -undefined dynamic_lookup -single_module -multiply_defined suppress -L/Library/Frameworks/R.framework/Resources/lib -L/usr/local/lib -o mclust.so mclust.o mclustaddson.o -L/Library/Frameworks/R.framework/Resources/lib -lRlapack -L/Library/Frameworks/R.framework/Resources/lib -lRblas -L/usr/local/lib/gcc/x86_64-apple-darwin13.0.0/4.8.2 -lgfortran -lquadmath -lm -L/usr/local/lib/gcc/x86_64-apple-darwin13.0.0/4.8.2 -lgfortran -lquadmath -lm -F/Library/Frameworks/R.framework/.. -framework R -Wl,-framework -Wl,CoreFoundation
ld: warning: directory not found for option '-L/usr/local/lib/gcc/x86_64-apple-darwin13.0.0/4.8.2'
ld: warning: directory not found for option '-L/usr/local/lib/gcc/x86_64-apple-darwin13.0.0/4.8.2'
ld: library not found for -lquadmath
clang: error: linker command failed with exit code 1 (use -v to see invocation)
make: *** [mclust.so] Error 1
ERROR: compilation failed for package ‘mclust’
* removing ‘/Library/Frameworks/R.framework/Versions/3.3/Resources/library/mclust’
Warning in install.packages :
  installation of package ‘mclust’ had non-zero exit status

I don't have /usr/local/lib/gcc/x86_64-apple-darwin13.0.0, so it makes sense that it can't be found. I have /usr/local/lib/gcc/i686-apple-darwin11 and /usr/local/lib/gcc/4.8 (symlink to Homebrew installation). Where is it getting x86_64-apple-darwin13.0.0 from?

There are a lot of references to a similar error online. However, all of them are related to compiling in Xcode and resolved by updating project settings, which is not applicable here.