报错如下：
cc -fno-strict-aliasing -fno-common -dynamic -g -Os -pipe -fno-common -fno-strict-aliasing -fwrapv -DENABLE_DTRACE -DMACOSX -DNDEBUG -Wall -Wstrict-prototypes -Wshorten-64-to-32 -DNDEBUG -g -fwrapv -Os -Wall -Wstrict-prototypes -DENABLE_DTRACE -Wno-error=unused-command-line-argument-hard-error-in-future -pipe -Wno-error=unused-command-line-argument-hard-error-in-future -I/usr/include/libxml2 -I/private/tmp/pip_build_root/lxml/src/lxml/includes -I/System/Library/Frameworks/Python.framework/Versions/2.7/include/python2.7 -c src/lxml/lxml.etree.c -o build/temp.macosx-10.10-intel-2.7/src/lxml/lxml.etree.o -w -flat_namespace
In file included from src/lxml/lxml.etree.c:239:
/private/tmp/pip_build_root/lxml/src/lxml/includes/etree_defs.h:14:10: fatal error: 'libxml/xmlversion.h' file not found
#include "libxml/xmlversion.h"
^
1 error generated.
error: command 'cc' failed with exit status 1
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首先确认使用了 brew 安装 install libxml2 and libxslt
执行以下命令：
xcode-select --install
sudo CPATH=/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.9.sdk/usr/include/libxml2 CFLAGS=-Qunused-arguments CPPFLAGS=-Qunused-arguments pip install lxml
我的Mac为 MacOSX10.10.sdk