Nope, treat warnings as errors is not enabled.
Some examples of these warnings are:
In file included from /home/conny/Desktop/projekt/code/src/cmapeditor/ceditorpalette.h:5,
from /home/conny/Desktop/projekt/code/src/cmapeditor/cmapeditor.h:11,
from src/capplication.h:10,
from main.cpp:3:
/home/conny/Desktop/projekt/code/src/cmapeditor/ceditorobject.h:17: warning: `
class CEditorObject' has virtual functions but non-virtual destructor
In file included from /home/conny/Desktop/projekt/code/src/cmapeditor/ceditorpalette.h:6,
from /home/conny/Desktop/projekt/code/src/cmapeditor/cmapeditor.h:11,
from src/capplication.h:10,
from main.cpp:3:
/home/conny/Desktop/projekt/code/src/cmapeditor/ceditorcurrentobject.h:11: warning: `
class CEditorCurrentObject' has virtual functions but non-virtual destructor
In file included from /home/conny/Desktop/projekt/code/src/cmapeditor/cmapeditor.h:11,
from src/capplication.h:10,
from main.cpp:3:
/home/conny/Desktop/projekt/code/src/cmapeditor/ceditorpalette.h:13: warning: `
class CEditorPalette' has virtual functions but non-virtual destructor
In file included from src/capplication.h:10,
from main.cpp:3:
/home/conny/Desktop/projekt/code/src/cmapeditor/cmapeditor.h:18: warning: `
class CMapEditor' has virtual functions but non-virtual destructor
In file included from src/capplication.h:11,
from main.cpp:3:
/home/conny/Desktop/projekt/code/src/cgame/cgame.h:13: warning: `class CGame'
has virtual functions but non-virtual destructor
Compiling src/capplication.cpp...
In file included from src/ctestcontext.h:9,
from src/capplication.h:6,
from src/capplication.cpp:1:
src/cbutton.h:6: warning: `class CButton' has virtual functions but non-virtual
destructor
In file included from /home/conny/Desktop/projekt/code/src/cmapeditor/ceditorpalette.h:5,
from /home/conny/Desktop/projekt/code/src/cmapeditor/cmapeditor.h:11,
from src/capplication.h:10,
from src/capplication.cpp:1:
/home/conny/Desktop/projekt/code/src/cmapeditor/ceditorobject.h:17: warning: `
class CEditorObject' has virtual functions but non-virtual destructor
In file included from /home/conny/Desktop/projekt/code/src/cmapeditor/ceditorpalette.h:6,
from /home/conny/Desktop/projekt/code/src/cmapeditor/cmapeditor.h:11,
from src/capplication.h:10,
from src/capplication.cpp:1:
/home/conny/Desktop/projekt/code/src/cmapeditor/ceditorcurrentobject.h:11: warning: `
class CEditorCurrentObject' has virtual functions but non-virtual destructor
src/cclickable.cc: In member function `virtual bool CClickable::checkOverlap()
':
src/cclickable.cc:24: warning: control reaches end of non-void function
Under build messages these are all reported as warnings, not errors.