"Error: Couldn't install: lxml 2.3.6"

Erro durante a compilação através do buildout, com virtualenv==1.7.2.

Using build configuration of libxslt 1.1.26
Building against libxml2/libxslt in the following directory: /usr/lib
gcc: internal compiler error: Morto (program cc1)
Please submit a full bug report,
with preprocessed source if appropriate.
See  for instructions.
error: Setup script exited with error: command 'gcc' failed with exit status 4
An error occurred when trying to install lxml 2.3.6. Look above this message for any errors that were output by easy_install.
While:
  Installing client1.
  Getting distribution for 'lxml==2.3.6'.
Error: Couldn't install: lxml 2.3.6

Building against libxml2/libxslt in one of the following directories:
  /opt/env-buildout/prod/8130-plone-stat-1408108765/parts/lxml/libxslt/lib
  /opt/env-buildout/prod/8130-plone-stat-1408108765/parts/lxml/libxml2/lib
gcc: internal compiler error: Morto (program cc1)
Please submit a full bug report,
with preprocessed source if appropriate.
See  for instructions.
error: Setup script exited with error: command 'gcc' failed with exit status 4
An error occurred when trying to install lxml 2.3.6. Look above this message for any errors that were output by easy_install.
While:
  Installing lxml.
Error: Couldn't install: lxml 2.3.6

Solução

Instalar o lxml==2.3.6 manualmente:
$ ./py27/bin/easy_install lxml==2.3.6