FileCheck: command not found

Have You tried accessing the binary with the full path?

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On Debian possible default full paths are:

/usr/lib/llvm-3.4/bin/FileCheck - from package: llvm-3.4-tools
/usr/lib/llvm-3.5/bin/FileCheck - from package: llvm-3.5-tools

You may install the required package with command apt-get install {package}
Error in other languages:
FileCheck: bevel nie gevind nie
FileCheck: comandă negăsită
FileCheck: comando não encontrado
FileCheck: commande introuvable
FileCheck: command not found
FileCheck: käsku ei ole
FileCheck: không tìm thấy lệnh
FileCheck: komanda nerasta
FileCheck: Kommando nicht gefunden.
FileCheck: kommandot finns inte
FileCheck: komut yok
FileCheck: nie znaleziono polecenia
FileCheck: níor aimsíodh an t-ordú
FileCheck: no se encontró la orden
FileCheck: no s'ha trobat l'ordre
FileCheck: opdracht niet gevonden
FileCheck: parancs nem található
FileCheck: perintah tidak ditemukan
FileCheck: príkaz nenájdený
FileCheck: příkaz nenalezen
FileCheck: команда не найдена
FileCheck: командата не е открита
FileCheck: 命令找不到
FileCheck: コマンドが見つかりません