系统版本：OS X 10.6.8，错误信息如下：

 TranchmatoMacBook:local tranch$ brew install freetype
Warning: Your Xcode (3.2.2) is outdated
Please update to Xcode 3.2.6.
Xcode can be updated from https://developer.apple.com/downloads/
clang version 1.0.2 (http://llvm.org/svn/llvm-project/cfe/tags/Apple/clang-32 exported)
Target: x86_64-apple-darwin10
==> Downloading https://downloads.sf.net/project/freetype/freetype2/2.5.2/freetype-2.5.2.tar.bz2
Already downloaded: /Library/Caches/Homebrew/freetype-2.5.2.tar.bz2
==> ./configure --prefix=/usr/local/Cellar/freetype/2.5.2
==> make
builds/unix/ftsystem.c:369: error: 'Cannot_Open_Stream' undeclared (first use in this function)
/private/tmp/freetype-zo03/freetype-2.5.2/src/base/ftdebug.c:46:10: error: #include expects "FILENAME" or <FILENAME>
make: *** [/private/tmp/freetype-zo03/freetype-2.5.2/objs/ftsystem.lo] Error 1
make: *** Waiting for unfinished jobs....
make: *** [/private/tmp/freetype-zo03/freetype-2.5.2/objs/ftdebug.lo] Error 1
Error: Homebrew doesn't know what compiler versions ship with your version
of Xcode (3.2.2). Please `brew update` and if that doesn't help, file
an issue with the output of `brew --config`:
  https://github.com/Homebrew/homebrew/issues

Note that we only track stable, released versions of Xcode.

Thanks!
clang version 1.0.2 (http://llvm.org/svn/llvm-project/cfe/tags/Apple/clang-32 exported)
Target: x86_64-apple-darwin10

READ THIS: https://github.com/Homebrew/homebrew/wiki/troubleshooting

These open issues may also help:
Fix podofo on Mavericks and freetype 2.5.1 (https://github.com/Homebrew/homebrew/pull/26888)
mplayer-1.1.1 builds but does not find freetype (no osd) (https://github.com/Homebrew/homebrew/issues/26126)