ext_texture_array-gen-mipmap: command not found

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

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

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 CentOS possible default full paths are:

/usr/lib64/piglit/bin/ext_texture_array-gen-mipmap - from package: piglit

You may install the required package with command yum install {package}

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