Frequently Asked Questions

Why do I get message that say “… GLIBCXX_3.4.20 not found …” when I try to run any application when XALT is active?

This means that your site has installed an GCC version newer than the default gcc installed on the system. Please re-install XALT with just the system version of gcc. If your system gcc is older than 4.8.5 (say Centos 6) then please see If your g++ is older than 4.8.5

Why when my site upgraded to Centos 7.5 and the latest OPA drivers for Intel’s Omni-Path and using Intel MPI, all XALT built programs have an error that looks like this?

c591-801.stampede2.tacc.utexas.edu.334447hfi_userinit: mmap of status page (dabbad0008030000) failed: Operation not permitted c591-801.stampede2.tacc.utexas.edu.334447hfp_gen1_context_open: hfi_userinit: failed, trying again (1/3)

This is because all programs built with XALT prior to version 2.5 caused the GNU Stack bit to be set. Please see XALT and the GNU Stack bit for a migration strategy.