I am trying to build the latest Python 2.7 (2.7.14_1) and it fails on freeBSD 10.3-RELEASE-p12, because of an undefined symbol "XML_ParserCreate_MM" in pyexpat. Last time I built Python 2.7.3 and everything was fine. The following errors are generated:

$portmaster lang/python
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building 'pyexpat' extension
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cc -shared -lpthread -L/usr/local/lib -Wl,-rpath,/usr/local/lib -fstack-protector -lpthread -L/usr/local/lib -Wl,-rpath,/usr/local/lib -fstack-protector -O2 -pipe -I/usr/local/include -fstack-protector -fno-strict-aliasing -I/usr/local/include -I/usr/local/include build/temp.freebsd-10.3-RELEASE-p12-amd64-2.7/var/ports/usr/ports/lang/python27/work/Python-2.7.14/Modules/pyexpat.o build/temp.freebsd-10.3-RELEASE-p12-amd64-2.7/var/ports/usr/ports/lang/python27/work/Python-2.7.14/Modules/expat/xmlparse.o build/temp.freebsd-10.3-RELEASE-p12-amd64-2.7/var/ports/usr/ports/lang/python27/work/Python-2.7.14/Modules/expat/xmlrole.o build/temp.freebsd-10.3-RELEASE-p12-amd64-2.7/var/ports/usr/ports/lang/python27/work/Python-2.7.14/Modules/expat/xmltok.o -L/usr/local/lib -L. -lpython2.7 -o build/lib.freebsd-10.3-RELEASE-p12-amd64-2.7/pyexpat.so
*** WARNING: renaming "pyexpat" since importing it failed: build/lib.freebsd-10.3-RELEASE-p12-amd64-2.7/pyexpat.so: Undefined symbol "XML_ParserCreate_MM"
building '_elementtree' extension
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cc -shared -lpthread -L/usr/local/lib -Wl,-rpath,/usr/local/lib -fstack-protector -lpthread -L/usr/local/lib -Wl,-rpath,/usr/local/lib -fstack-protector -O2 -pipe -I/usr/local/include -fstack-protector -fno-strict-aliasing -I/usr/local/include -I/usr/local/include build/temp.freebsd-10.3-RELEASE-p12-amd64-2.7/var/ports/usr/ports/lang/python27/work/Python-2.7.14/Modules/_elementtree.o -L/usr/local/lib -L. -lpython2.7 -o build/lib.freebsd-10.3-RELEASE-p12-amd64-2.7/_elementtree.so
*** WARNING: renaming "_elementtree" since importing it failed: PyCapsule_Import could not import module "pyexpat"
...
Failed to build these modules:
_elementtree       pyexpat
...
===>   Registering installation for python27-2.7.14_1 as automatic
pkg-static: Unable to access file /var/ports/usr/ports/lang/python27/work/stage/usr/local/lib/python2.7/lib-dynload/_elementtree.so:No such file or directory
pkg-static: Unable to access file /var/ports/usr/ports/lang/python27/work/stage/usr/local/lib/python2.7/lib-dynload/pyexpat.so:No such file or directory
*** Error code 74