This Article Represents a Troubleshooting of Qt Creator Building Issue/Error:
“cannot Find -lGL”.
The Content give Focus Only to the Essentials Instructions and Commands to make it Easier to Follow.

Open Terminal Window
(Press “Enter” to Execute Commands)Make a Symbolic Link
For 32 bit Systems
ln -s /usr/lib/libGL.so.1 /usr/lib/libGL.so
For 64 bit Systems
ln -s /usr/lib64/libGL.so.1 /usr/lib64/libGL.so