Fix python to build with newlib.

libraries/python/nacl-python.sh

 #!/bin/bash
 # Copyright (c) 2013 The Native Client Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 source pkg_info
 source ../../build_tools/common.sh
 
 EXECUTABLES=python.nexe
 # Currently this package only builds on linux.
 # The build relies on certain host binaries and pythong's configure
 # requires us to sett --build= as well as --host=.
-EXTRA_CONFIGURE_ARGS="--disable-ipv6 --with-suffix=.nexe --build=x86_64-linux-gnu"
-export MAKEFLAGS="PGEN=../build-nacl-host/Parser/pgen"
 HERE=$(cd "$(dirname "$BASH_SOURCE")" ; pwd)
 
 BuildHostPython() {
   ChangeDir ${NACL_PACKAGES_REPOSITORY}/${PACKAGE_DIR}
   MakeDir build-nacl-host
   ChangeDir build-nacl-host
-  LogExecute ../configure
+  if [ -f python -a -f Parser/pgen ]; then
+    return
+  fi
+  # Reset CFLAGS and LDFLAGS when configuring the host
+  # version of python since they hold values designed for
+  # building for NaCl.
+  CFLAGS="" LDFLAGS="" LogExecute ../configure
   LogExecute make -j${OS_JOBS} python Parser/pgen
 }
 
 CustomConfigureStep() {
   BuildHostPython
   export CROSS_COMPILE=true
   # We pre-seed configure with certain results that it cannot determine
   # since we are doing a cross compile.  The $CONFIG_SITE file is sourced
   # by configure early on.
   export CONFIG_SITE=${HERE}/config.site
+  # Disable ipv6 since configure claims it requires a working getaddrinfo
+  # which we do not provide.  TODO(sbc): remove this once nacl_io supports
+  # getaddrinfo.
+  EXTRA_CONFIGURE_ARGS="--disable-ipv6"
+  EXTRA_CONFIGURE_ARGS+=" --with-suffix=.nexe"
+  EXTRA_CONFIGURE_ARGS+=" --build=x86_64-linux-gnu"
+  export MAKEFLAGS="PGEN=../build-nacl-host/Parser/pgen"
+  export LIBS="-lc -lnosys"
   DefaultConfigureStep
 }
 
 CustomTestStep() {
   WriteSelLdrScript python python.nexe
 }
 
 CustomPackageInstall() {
   DefaultPreInstallStep
   DefaultDownloadStep
   DefaultExtractStep
   DefaultPatchStep
   CustomConfigureStep
   DefaultBuildStep
   DefaultTranslateStep
   DefaultValidateStep
   CustomTestStep
   DefaultInstallStep
 }
 
 CustomPackageInstall
 exit 0