gistfile1.txt

Warning: Unbrewed dylibs were found in /usr/local/lib
You have unbrewed dylibs in /usr/local/lib. If you didn't put them there on purpose,
they could cause problems when building Homebrew formulae.

Unexpected dylibs (delete if they are no longer needed):
    /usr/local/lib/libonig.2.0.0.dylib
    /usr/local/lib/libsane.1.0.21.dylib

You changed your cc to symlink to llvm.
This bypasses LLVM checks, and some formulae may mysteriously fail to work.
You may want to change /usr/bin/cc to point back at gcc.

To force Homebrew to use LLVM, you can set the "HOMEBREW_LLVM" environmental
variable, or pass "--use-lvm" to "brew install".