Qt: can't find -lGL error
I just reinstalled QtCreator, created new project (Qt Application) an got this after compilation:
/usr/bin/ld: **cannot find -lGL**
collect2: error: ld returned 1 exit status
make: *** [untitled1] Error 1
18:07:41: The process "/usr/bin/make" exited with code 2.
Error while building/deploying project untitled1 (kit: Desktop Qt 5.1.0 GCC 32bit)
When executing step 'Make'
(Project is empty, I did'n commit any changes)
Qt Creator 2.7.2
Based on Qt 5.1.0 (32 bit)
Ubuntu 13.04
How do I solve this problem?
Solution 1:
You should install package "libgl1-mesa-dev":
sudo apt install libgl1-mesa-dev
Solution 2:
you don't need to install anything. libGL is already installed with Ubuntu, you just need to soft link it. (tested for ubuntu 14.x and 15.x, might work for later versions)
- First locate the GL library
- Then link it under /usr/lib
- If the library is missing, it can be installed via libgl1-mesa-dev package
Here is how you could do this:
$ locate libGL
/usr/lib/i386-linux-gnu/mesa/libGL.so.1
/usr/lib/i386-linux-gnu/mesa/libGL.so.1.2.0
/usr/lib/x86_64-linux-gnu/libGLEW.so.1.10
/usr/lib/x86_64-linux-gnu/libGLEW.so.1.10.0
/usr/lib/x86_64-linux-gnu/libGLEWmx.so.1.10
/usr/lib/x86_64-linux-gnu/libGLEWmx.so.1.10.0
/usr/lib/x86_64-linux-gnu/libGLU.so.1
/usr/lib/x86_64-linux-gnu/libGLU.so.1.3.1
/usr/lib/x86_64-linux-gnu/mesa/libGL.so.1
/usr/lib/x86_64-linux-gnu/mesa/libGL.so.1.2.0
/usr/lib/x86_64-linux-gnu/mesa-egl/libGLESv2.so.2
/usr/lib/x86_64-linux-gnu/mesa-egl/libGLESv2.so.2.0.0
$ sudo ln -s /usr/lib/x86_64-linux-gnu/mesa/libGL.so.1 /usr/lib/libGL.so
Solution 3:
The gui Qt module is included by default. If you don't want to use it in a project (e.g., it is a library or only uses stdio), you need to specify that in the .pro file.
QT -= gui
And the linker won't attempt to find lGL regardless of whether it is installed.
My case is admittedly a bit odd, since the main reason to use Qt is to create gui's. Installing the GL library is certainly not difficult, I just wanted to know why my quick and dirty Hello World wanted it.
Solution 4:
write:
yum provides */libGL.so
after providing:
yum install mesa-libGL-devel mesa-libGLU-devel
Solution 5:
This worked for me:
sudo ln -s /usr/lib/libEGL1.so /usr/lib/libGL.so