pp-trace: 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/pp-trace - from package: clang-3.4
/usr/lib/llvm-3.5/bin/pp-trace - from package: clang-3.5
/usr/bin/pp-trace - from package: clang

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