It appears that 3.4.4 was released with wheels which pip chooses to install instead of trying to compile the tar.gz.
Versions of things:
Python : sys.version_info(major=2, minor=7, micro=6, releaselevel='final', serial=0)
lxml.etree : (3, 4, 4, 0)
libxml used : (2, 9, 0)
libxml compiled : (2, 9, 0)
libxslt used : (1, 1, 28)
libxslt compiled : (1, 1, 28)
Output from pip:
C:\>pip install -U lxml --no-cache-dir
Collecting lxml
Downloading lxml-3.5.0.tar.gz (3.8MB)
100% |################################| 3.8MB 2.7MB/s
Installing collected packages: lxml
Found existing installation: lxml 3.4.4
Uninstalling lxml-3.4.4:
Successfully uninstalled lxml-3.4.4
Running setup.py install for lxml
Complete output from command c:\python27\python.exe -c "import setuptools, tokenize;__file__='c:\\users\\martynhe\\appdata\\local\\temp\\pip-build-9dyzh1\\lxml\\setup.py';exec(compile(getattr(tokenize, 'open', open)(__file__).read().replace('\r\n', '\n'), __file__, 'exec'))" install --record c:\users\martynhe\appdata\local\temp\pip-kad7ph-record\install-record.txt --single-version-externally-managed --compile:
Building lxml version 3.5.0.
Building without Cython.
ERROR: 'xslt-config' is not recognized as an internal or external command,
operable program or batch file.
** make sure the development packages of libxml2 and libxslt are installed **
Using build configuration of libxslt
running install
running build
running build_py
creating build
creating build\lib.win32-2.7
creating build\lib.win32-2.7\lxml
copying src\lxml\builder.py -> build\lib.win32-2.7\lxml
copying src\lxml\cssselect.py -> build\lib.win32-2.7\lxml
copying src\lxml\doctestcompare.py -> build\lib.win32-2.7\lxml
copying src\lxml\ElementInclude.py -> build\lib.win32-2.7\lxml
copying src\lxml\pyclasslookup.py -> build\lib.win32-2.7\lxml
copying src\lxml\sax.py -> build\lib.win32-2.7\lxml
copying src\lxml\usedoctest.py -> build\lib.win32-2.7\lxml
copying src\lxml\_elementpath.py -> build\lib.win32-2.7\lxml
copying src\lxml\__init__.py -> build\lib.win32-2.7\lxml
creating build\lib.win32-2.7\lxml\includes
copying src\lxml\includes\__init__.py -> build\lib.win32-2.7\lxml\includes
creating build\lib.win32-2.7\lxml\html
copying src\lxml\html\builder.py -> build\lib.win32-2.7\lxml\html
copying src\lxml\html\clean.py -> build\lib.win32-2.7\lxml\html
copying src\lxml\html\defs.py -> build\lib.win32-2.7\lxml\html
copying src\lxml\html\diff.py -> build\lib.win32-2.7\lxml\html
copying src\lxml\html\ElementSoup.py -> build\lib.win32-2.7\lxml\html
copying src\lxml\html\formfill.py -> build\lib.win32-2.7\lxml\html
copying src\lxml\html\html5parser.py -> build\lib.win32-2.7\lxml\html
copying src\lxml\html\soupparser.py -> build\lib.win32-2.7\lxml\html
copying src\lxml\html\usedoctest.py -> build\lib.win32-2.7\lxml\html
copying src\lxml\html\_diffcommand.py -> build\lib.win32-2.7\lxml\html
copying src\lxml\html\_html5builder.py -> build\lib.win32-2.7\lxml\html
copying src\lxml\html\_setmixin.py -> build\lib.win32-2.7\lxml\html
copying src\lxml\html\__init__.py -> build\lib.win32-2.7\lxml\html
creating build\lib.win32-2.7\lxml\isoschematron
copying src\lxml\isoschematron\__init__.py -> build\lib.win32-2.7\lxml\isoschematron
copying src\lxml\lxml.etree.h -> build\lib.win32-2.7\lxml
copying src\lxml\lxml.etree_api.h -> build\lib.win32-2.7\lxml
copying src\lxml\includes\c14n.pxd -> build\lib.win32-2.7\lxml\includes
copying src\lxml\includes\config.pxd -> build\lib.win32-2.7\lxml\includes
copying src\lxml\includes\dtdvalid.pxd -> build\lib.win32-2.7\lxml\includes
copying src\lxml\includes\etreepublic.pxd -> build\lib.win32-2.7\lxml\includes
copying src\lxml\includes\htmlparser.pxd -> build\lib.win32-2.7\lxml\includes
copying src\lxml\includes\relaxng.pxd -> build\lib.win32-2.7\lxml\includes
copying src\lxml\includes\schematron.pxd -> build\lib.win32-2.7\lxml\includes
copying src\lxml\includes\tree.pxd -> build\lib.win32-2.7\lxml\includes
copying src\lxml\includes\uri.pxd -> build\lib.win32-2.7\lxml\includes
copying src\lxml\includes\xinclude.pxd -> build\lib.win32-2.7\lxml\includes
copying src\lxml\includes\xmlerror.pxd -> build\lib.win32-2.7\lxml\includes
copying src\lxml\includes\xmlparser.pxd -> build\lib.win32-2.7\lxml\includes
copying src\lxml\includes\xmlschema.pxd -> build\lib.win32-2.7\lxml\includes
copying src\lxml\includes\xpath.pxd -> build\lib.win32-2.7\lxml\includes
copying src\lxml\includes\xslt.pxd -> build\lib.win32-2.7\lxml\includes
copying src\lxml\includes\etree_defs.h -> build\lib.win32-2.7\lxml\includes
copying src\lxml\includes\lxml-version.h -> build\lib.win32-2.7\lxml\includes
creating build\lib.win32-2.7\lxml\isoschematron\resources
creating build\lib.win32-2.7\lxml\isoschematron\resources\rng
copying src\lxml\isoschematron\resources\rng\iso-schematron.rng -> build\lib.win32-2.7\lxml\isoschematron\resources\rng
creating build\lib.win32-2.7\lxml\isoschematron\resources\xsl
copying src\lxml\isoschematron\resources\xsl\RNG2Schtrn.xsl -> build\lib.win32-2.7\lxml\isoschematron\resources\xsl
copying src\lxml\isoschematron\resources\xsl\XSD2Schtrn.xsl -> build\lib.win32-2.7\lxml\isoschematron\resources\xsl
creating build\lib.win32-2.7\lxml\isoschematron\resources\xsl\iso-schematron-xslt1
copying src\lxml\isoschematron\resources\xsl\iso-schematron-xslt1\iso_abstract_expand.xsl -> build\lib.win32-2.7\lxml\isoschematron\resources\xsl\iso-schematron-xslt1
copying src\lxml\isoschematron\resources\xsl\iso-schematron-xslt1\iso_dsdl_include.xsl -> build\lib.win32-2.7\lxml\isoschematron\resources\xsl\iso-schematron-xslt1
copying src\lxml\isoschematron\resources\xsl\iso-schematron-xslt1\iso_schematron_message.xsl -> build\lib.win32-2.7\lxml\isoschematron\resources\xsl\iso-schematron-xslt1
copying src\lxml\isoschematron\resources\xsl\iso-schematron-xslt1\iso_schematron_skeleton_for_xslt1.xsl -> build\lib.win32-2.7\lxml\isoschematron\resources\xsl\iso-schematron-xslt1
copying src\lxml\isoschematron\resources\xsl\iso-schematron-xslt1\iso_svrl_for_xslt1.xsl -> build\lib.win32-2.7\lxml\isoschematron\resources\xsl\iso-schematron-xslt1
copying src\lxml\isoschematron\resources\xsl\iso-schematron-xslt1\readme.txt -> build\lib.win32-2.7\lxml\isoschematron\resources\xsl\iso-schematron-xslt1
running build_ext
building 'lxml.etree' extension
creating build\temp.win32-2.7
creating build\temp.win32-2.7\Release
creating build\temp.win32-2.7\Release\src
creating build\temp.win32-2.7\Release\src\lxml
C:\Users\martynhe\AppData\Local\Programs\Common\Microsoft\Visual C++ for Python\9.0\VC\Bin\cl.exe /c /nologo /Ox /MD /W3 /GS- /DNDEBUG -Isrc\lxml\includes -Ic:\python27\include -Ic:\python27\PC /Tcsrc\lxml\lxml.etree.c /Fobuild\temp.win32-2.7\Release\src\lxml\lxml.etree.obj -w
cl : Command line warning D9025 : overriding '/W3' with '/w'
lxml.etree.c
src\lxml\includes\etree_defs.h(14) : fatal error C1083: Cannot open include file: 'libxml/xmlversion.h': No such file or directory
Compile failed: command '"C:\Users\martynhe\AppData\Local\Programs\Common\Microsoft\Visual C++ for Python\9.0\VC\Bin\cl.exe"' failed with exit status 2
creating users
creating users\martynhe
creating users\martynhe\appdata
creating users\martynhe\appdata\local
creating users\martynhe\appdata\local\temp
C:\Users\martynhe\AppData\Local\Programs\Common\Microsoft\Visual C++ for Python\9.0\VC\Bin\cl.exe /c /nologo /Ox /MD /W3 /GS- /DNDEBUG -I/usr/include/libxml2 /Tcc:\users\martynhe\appdata\local\temp\xmlXPathInitaywdip.c /Fousers\martynhe\appdata\local\temp\xmlXPathInitaywdip.obj
xmlXPathInitaywdip.c
c:\users\martynhe\appdata\local\temp\xmlXPathInitaywdip.c(1) : fatal error C1083: Cannot open include file: 'libxml/xpath.h': No such file or directory
*********************************************************************************
Could not find function xmlCheckVersion in library libxml2. Is libxml2 installed?
*********************************************************************************
error: command '"C:\Users\martynhe\AppData\Local\Programs\Common\Microsoft\Visual C++ for Python\9.0\VC\Bin\cl.exe"' failed with exit status 2
----------------------------------------
Rolling back uninstall of lxml
Command "c:\python27\python.exe -c "import setuptools, tokenize;__file__='c:\\users\\martynhe\\appdata\\local\\temp\\pip-build-9dyzh1\\lxml\\setup.py';exec(compile(getattr(tokenize, 'open', open)(__file__).read().replace('\r\n', '\n'), __file__, 'exec'))" install --record c:\users\martynhe\appdata\local\temp\pip-kad7ph-record\install-record.txt --single-version-externally-managed --compile" failed with error code 1 in c:\users\martynhe\appdata\local\temp\pip-build-9dyzh1\lxml
