Cross posting for the benefit of others. See original thread here: http://software.intel.com/forums/topic/505599
A defect was reported with the Intel® Integrated Performance Primitives (IPP) 8.1 Initial release ippvars.csh file distributed for Linux* (found under: /opt/intel/composer_xe_2013_sp1/ipp).
This may also affect users who install the Intel® Composer XE 2013 SP1 Update 2 release (Package id: l_ccompxe_2013_sp1.2.144) and use the compilervars.csh script (found under: /opt/intel/composer_xe_2013_sp1/bin).
$ cd /opt/intel/composer_xe_2013_sp1.2.144/bin
$ source ./compilervars.csh intel64
arch: Undefined variable.
Refer to following article for a complete description of the error and work around: