/usr/share/SuperCollider/SCClassLibrary/JITLib/ is in supercollider-common 1:3.4.5-1wheezy1.
This file is owned by root:root, with mode 0o755.
..
/usr/share/SuperCollider/SCClassLibrary/JITLib/GUI/
/usr/share/SuperCollider/SCClassLibrary/JITLib/GUI/EnvirGui.sc
/usr/share/SuperCollider/SCClassLibrary/JITLib/GUI/JITGui.sc
/usr/share/SuperCollider/SCClassLibrary/JITLib/GUI/MonitorGui.sc
/usr/share/SuperCollider/SCClassLibrary/JITLib/GUI/NdefGui.sc
/usr/share/SuperCollider/SCClassLibrary/JITLib/GUI/NdefParamGui.sc
/usr/share/SuperCollider/SCClassLibrary/JITLib/GUI/NodeProxyEditor.sc
/usr/share/SuperCollider/SCClassLibrary/JITLib/GUI/ProxyMixer.sc
/usr/share/SuperCollider/SCClassLibrary/JITLib/GUI/ProxyMixerOld.sc
/usr/share/SuperCollider/SCClassLibrary/JITLib/GUI/ProxyMonitorGui.sc
/usr/share/SuperCollider/SCClassLibrary/JITLib/GUI/TaskProxyGui.sc
/usr/share/SuperCollider/SCClassLibrary/JITLib/GUI/extJITgui.sc
/usr/share/SuperCollider/SCClassLibrary/JITLib/GUI/extSoftSet.sc
/usr/share/SuperCollider/SCClassLibrary/JITLib/Patterns/
/usr/share/SuperCollider/SCClassLibrary/JITLib/Patterns/Fdef.sc
/usr/share/SuperCollider/SCClassLibrary/JITLib/Patterns/OpFunctionProxy.sc
/usr/share/SuperCollider/SCClassLibrary/JITLib/Patterns/Pdef.sc
/usr/share/SuperCollider/SCClassLibrary/JITLib/Patterns/Psym.sc
/usr/share/SuperCollider/SCClassLibrary/JITLib/Patterns/Pxfade.sc
/usr/share/SuperCollider/SCClassLibrary/JITLib/Patterns/extFunction.sc
/usr/share/SuperCollider/SCClassLibrary/JITLib/Patterns/extRoutine.sc
/usr/share/SuperCollider/SCClassLibrary/JITLib/ProxySpace/
/usr/share/SuperCollider/SCClassLibrary/JITLib/ProxySpace/BusPlug.sc
/usr/share/SuperCollider/SCClassLibrary/JITLib/ProxySpace/InBus.sc
/usr/share/SuperCollider/SCClassLibrary/JITLib/ProxySpace/NodeMap.sc
/usr/share/SuperCollider/SCClassLibrary/JITLib/ProxySpace/NodeMapSetting.sc
/usr/share/SuperCollider/SCClassLibrary/JITLib/ProxySpace/NodeProxy.sc
/usr/share/SuperCollider/SCClassLibrary/JITLib/ProxySpace/ProxyInterfaces.sc
/usr/share/SuperCollider/SCClassLibrary/JITLib/ProxySpace/ProxySpace.sc
/usr/share/SuperCollider/SCClassLibrary/JITLib/ProxySpace/ProxySynthDef.sc
/usr/share/SuperCollider/SCClassLibrary/JITLib/ProxySpace/TempoBusClock.sc
/usr/share/SuperCollider/SCClassLibrary/JITLib/ProxySpace/extStoreOn.sc
/usr/share/SuperCollider/SCClassLibrary/JITLib/ProxySpace/operators.sc
/usr/share/SuperCollider/SCClassLibrary/JITLib/ProxySpace/wrapForNodeProxy.sc