$ brew doctor
Warning: An "autoconf" in your path blocks the Xcode-provided version at:
  /usr/local/Cellar/autoconf

This custom autoconf may cause some Homebrew formulae to fail to compile.

Warning: Broken symlinks were found. Remove them with `brew prune`:
  /usr/local/bin/remote_api_shell.py
  /usr/local/bin/dev_appserver.py
  /usr/local/bin/bulkloader.py
  /usr/local/bin/bulkload_client.py
  /usr/local/bin/appcfg.py

Warning: "config" scripts exist outside your system or Homebrew directories.
`./configure` scripts often look for *-config scripts to determine if
software packages are installed, and what additional flags to use when
compiling and linking.

Having additional scripts in your path can confuse software installed via
Homebrew if the config script overrides a system or Homebrew provided
script of the same name. We found the following "config" scripts:

    /Library/Frameworks/Python.framework/Versions/Current/bin/python-config
    /Library/Frameworks/Python.framework/Versions/Current/bin/python2-config
    /Library/Frameworks/Python.framework/Versions/Current/bin/python2.7-config
    /Library/Frameworks/Python.framework/Versions/Current/bin/wx-config
    /Library/Frameworks/Python.framework/Versions/2.7/bin/python-config
    /Library/Frameworks/Python.framework/Versions/2.7/bin/python2.7-config

Warning: Enthought Python was found in your PATH.
This can cause build problems, as this software installs its own
copies of iconv and libxml2 into directories that are picked up by
other build systems.

Warning: gettext files detected at a system prefix
These files can cause compilation and link failures, especially if they
are compiled with improper architectures. Consider removing these files:
    /usr/local/lib/libintl.dylib

Warning: An outdated version of Git was detected in your PATH.
Git 1.7.10 or newer is required to perform checkouts over HTTPS from GitHub.
Please upgrade: brew upgrade git

Warning: Your XQuartz (2.5.3) is outdated
Please install XQuartz 2.7.5:
  https://xquartz.macosforge.org

Warning: You may have installed MacGPG2 via the package installer.
Several other checks in this script will turn up problems, such as stray
dylibs in /usr/local and permissions issues with share and man in /usr/local/.

Warning: Unbrewed dylibs were found in /usr/local/lib.
If you didn't put them there on purpose they could cause problems when
building Homebrew formulae, and may need to be deleted.

Unexpected dylibs:
    /usr/local/lib/libatk-1.0.0.2209.1.dylib
    /usr/local/lib/libcdt.5.dylib
    /usr/local/lib/libcgraph.6.dylib
    /usr/local/lib/libfst.0.dylib
    /usr/local/lib/libfstscript.0.dylib
    /usr/local/lib/libgdk-x11-2.0.0.1200.0.dylib
    /usr/local/lib/libgdk_pixbuf-2.0.0.1200.0.dylib
    /usr/local/lib/libgdk_pixbuf_xlib-2.0.0.1200.0.dylib
    /usr/local/lib/libgio-2.0.0.0.0.dylib
    /usr/local/lib/libGLEW.1.5.4.dylib
    /usr/local/lib/libglib-2.0.0.1600.0.dylib
    /usr/local/lib/libgmodule-2.0.0.1600.0.dylib
    /usr/local/lib/libgnt.0.dylib
    /usr/local/lib/libgobject-2.0.0.1600.0.dylib
    /usr/local/lib/libgraph.5.dylib
    /usr/local/lib/libgthread-2.0.0.1600.0.dylib
    /usr/local/lib/libgtk-x11-2.0.0.1200.0.dylib
    /usr/local/lib/libgvc.6.dylib
    /usr/local/lib/libgvpr.2.dylib
    /usr/local/lib/libintl.8.0.2.dylib
    /usr/local/lib/libjpeg.62.dylib
    /usr/local/lib/libksba.8.dylib
    /usr/local/lib/libpango-1.0.0.2100.0.dylib
    /usr/local/lib/libpangocairo-1.0.0.2100.0.dylib
    /usr/local/lib/libpangoft2-1.0.0.2100.0.dylib
    /usr/local/lib/libpangox-1.0.0.2100.0.dylib
    /usr/local/lib/libpangoxft-1.0.0.2100.0.dylib
    /usr/local/lib/libpathplan.4.dylib
    /usr/local/lib/libportaudio.2.0.0.dylib
    /usr/local/lib/libpth.20.0.27.dylib
    /usr/local/lib/libpurple.0.dylib
    /usr/local/lib/libSDL-1.2.0.dylib
    /usr/local/lib/libwx_baseu-2.9.1.0.0.dylib
    /usr/local/lib/libwx_baseu_net-2.9.1.0.0.dylib
    /usr/local/lib/libwx_baseu_xml-2.9.1.0.0.dylib
    /usr/local/lib/libwx_osx_cocoau_adv-2.9.1.0.0.dylib
    /usr/local/lib/libwx_osx_cocoau_aui-2.9.1.0.0.dylib
    /usr/local/lib/libwx_osx_cocoau_core-2.9.1.0.0.dylib
    /usr/local/lib/libwx_osx_cocoau_gl-2.9.1.0.0.dylib
    /usr/local/lib/libwx_osx_cocoau_html-2.9.1.0.0.dylib
    /usr/local/lib/libwx_osx_cocoau_media-2.9.1.0.0.dylib
    /usr/local/lib/libwx_osx_cocoau_propgrid-2.9.1.0.0.dylib
    /usr/local/lib/libwx_osx_cocoau_qa-2.9.1.0.0.dylib
    /usr/local/lib/libwx_osx_cocoau_ribbon-2.9.1.0.0.dylib
    /usr/local/lib/libwx_osx_cocoau_richtext-2.9.1.0.0.dylib
    /usr/local/lib/libwx_osx_cocoau_stc-2.9.1.0.0.dylib
    /usr/local/lib/libwx_osx_cocoau_xrc-2.9.1.0.0.dylib
    /usr/local/lib/libxdot.4.dylib
    /usr/local/lib/libz.1.2.5.dylib

Warning: Unbrewed .la files were found in /usr/local/lib.
If you didn't put them there on purpose they could cause problems when
building Homebrew formulae, and may need to be deleted.

Unexpected .la files:
    /usr/local/lib/libatk-1.0.la
    /usr/local/lib/libfst.la
    /usr/local/lib/libfstscript.la
    /usr/local/lib/libgdk-x11-2.0.la
    /usr/local/lib/libgdk_pixbuf-2.0.la
    /usr/local/lib/libgdk_pixbuf_xlib-2.0.la
    /usr/local/lib/libgio-2.0.la
    /usr/local/lib/libglib-2.0.la
    /usr/local/lib/libgmodule-2.0.la
    /usr/local/lib/libgnt.la
    /usr/local/lib/libgobject-2.0.la
    /usr/local/lib/libgthread-2.0.la
    /usr/local/lib/libgtk-x11-2.0.la
    /usr/local/lib/libintl.la
    /usr/local/lib/libjpeg.la
    /usr/local/lib/libksba.la
    /usr/local/lib/libpango-1.0.la
    /usr/local/lib/libpangocairo-1.0.la
    /usr/local/lib/libpangoft2-1.0.la
    /usr/local/lib/libpangox-1.0.la
    /usr/local/lib/libpangoxft-1.0.la
    /usr/local/lib/libportaudio.la
    /usr/local/lib/libpth.la
    /usr/local/lib/libpurple.la

Warning: Unbrewed .pc files were found in /usr/local/lib/pkgconfig.
If you didn't put them there on purpose they could cause problems when
building Homebrew formulae, and may need to be deleted.

Unexpected .pc files:
    /usr/local/lib/pkgconfig/finch.pc
    /usr/local/lib/pkgconfig/fuse.pc
    /usr/local/lib/pkgconfig/gnt.pc
    /usr/local/lib/pkgconfig/libcdt.pc
    /usr/local/lib/pkgconfig/libcgraph.pc
    /usr/local/lib/pkgconfig/libgraph.pc
    /usr/local/lib/pkgconfig/libgvc.pc
    /usr/local/lib/pkgconfig/libgvpr.pc
    /usr/local/lib/pkgconfig/libpathplan.pc
    /usr/local/lib/pkgconfig/libxdot.pc
    /usr/local/lib/pkgconfig/purple.pc

Warning: Unbrewed static libraries were found in /usr/local/lib.
If you didn't put them there on purpose they could cause problems when
building Homebrew formulae, and may need to be deleted.

Unexpected static libraries:
    /usr/local/lib/libGLEW.a
    /usr/local/lib/libintl.a
    /usr/local/lib/liblua.a
    /usr/local/lib/libportaudio.a
    /usr/local/lib/libpth.a

Warning: Some installed formula are missing dependencies.
You should `brew install` the missing dependencies:

    brew install gmp nettle rbenv

Run `brew missing` for more details.

Warning: You have a non-Homebrew 'pkg-config' in your PATH:
  /usr/local/Cellar/pkg-config

`./configure` may have problems finding brew-installed packages using
this other pkg-config.