matplotlib安装错误，怀疑为gcc

我正试图在MacBook Pro 10.8.3上安装

matplotlib

。我所有的科学软件包（python、qgis和许多其他软件包）都是用自制软件安装的<代码>pip安装matplotlib失败，出现以下错误：

ld: library not found for -lgcc_ext.10.5
collect2: error: ld returned 1 exit status
error: command 'c++' failed with exit status 1

我搞不懂这部lgcc_ext.10.5是在找什么。我见过其他问题，例如，但我的错误似乎不同。它发生在

pip安装

或通过

git克隆安装

Downloading/unpacking matplotlib
  Downloading matplotlib-1.2.1.tar.gz (38.4MB): 38.4MB downloaded
  Running setup.py egg_info for package matplotlib
    basedirlist is: ['/usr/local/', '/usr', '/usr/X11', '/opt/local']
    ============================================================================
BUILDING MATPLOTLIB
            matplotlib: 1.2.1
                python: 2.7.5 (default, May 21 2013, 10:35:49)  [GCC 4.2.1
                        Compatible Apple LLVM 4.2 (clang-425.0.24)]
              platform: darwin

REQUIRED DEPENDENCIES
                 numpy: 1.6.2
             freetype2: 16.0.10

OPTIONAL BACKEND DEPENDENCIES
                libpng: 1.5.14
               Tkinter: Tkinter: 81008, Tk: 8.5, Tcl: 8.5
            pkg-config: looking for pygtk-2.0 gtk+-2.0
                        * Package libffi was not found in the pkg-config
                        * search path. Perhaps you should add the directory
                        * containing `libffi.pc' to the PKG_CONFIG_PATH
                        * environment variable Package 'libffi', required by
                        * 'pygobject-2.0', not found
                        * You may need to install 'dev' package(s) to
                        * provide header files.
                  Gtk+: no
                        * Could not find Gtk+ headers in any of
                        * '/usr/local/include', '/usr/include',
                        * '/usr/X11/include', '/opt/local/include',
                        * '/usr/local/include', '/usr/include',
                        * '/usr/X11/include', '.'
       Mac OS X native: yes
                    Qt: no
                   Qt4: Qt: 4.8.4, PyQt4: 4.10.1
                PySide: Qt: 4.8.4, PySide: 1.1.2
                 Cairo: 1.10.0

OPTIONAL DATE/TIMEZONE DEPENDENCIES
              dateutil: matplotlib will provide
                  pytz: matplotlib will provide

OPTIONAL USETEX DEPENDENCIES
                dvipng: 1.14
           ghostscript: 9.07
                 latex: 3.1415926
               pdftops: 0.22.4

[Edit setup.cfg to suppress the above messages]
============================================================================

我的完整输出非常长，但我收到了一些我不知道与之相关的警告，例如：

cc -DNDEBUG -g -fwrapv -O3 -Wall -I/usr/X11/include -I/usr/X11/include/freetype2 -I/usr/X11/include/libpng12 -DPY_ARRAY_UNIQUE_SYMBOL=MPL_ARRAY_API -DPYCXX_ISO_CPP_LIB=1 -I/usr/local/include -I/usr/include -I/usr/X11/include -I/opt/local/include -I/Library/Python/2.7/site-packages/numpy-override/numpy/core/include -I/usr/local/Cellar/freetype/2.4.11/include/freetype2 -I/usr/local/Cellar/freetype/2.4.11/include -I/usr/local/include -I/usr/include -I/usr/X11/include -I. -I/usr/local/Cellar/python/2.7.5/Frameworks/Python.framework/Versions/2.7/include/python2.7 -c CXX/cxxsupport.cxx -o build/temp.macosx-10.8-x86_64-2.7/CXX/cxxsupport.o

In file included from CXX/cxxsupport.cxx:40:

In file included from CXX/Python2/cxxsupport.cxx:38:

In file included from ./CXX/Objects.hxx:40:

./CXX/Python2/Objects.hxx:1133:23: warning: implicit conversion of NULL constant to 'int' [-Wnull-conversion]

            , offset( NULL )

                    ~ ^~~~

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