523ffcc702
This started to happen after #4277, problem is when parsing fails treeRoot can point ot non Leaf objects. This does not happens when parsing from the DataFilter constructor since treeRoot is forced to NULL on errors, this commit does the same for check and parseFilter. Remaining problem is the memory leak in these cases, which are frequent when editing filters in User or LTM charts as explained in #4249
GoldenCheetah
About
GoldenCheetah is a desktop application for cyclists and triathletes and coaches, providing a rich set of tools and models to analyse, track and predict performance, optimise aerodynamics and train indoors.
GoldenCheetah integrates with most popular cloud services like Strava and Todays Plan, imports data from bike computers, imports downloads from any website like TrainingPeaks and Garmin and will also connect to smart trainers using ANT+ and Bluetooth.
GoldenCheetah is free for everyone to use and modify, released under the GPL v2 open source license with pre-built binaries for Mac, Windows and Linux.
Installing
Golden Cheetah install and build instructions are documented for each platform;
INSTALL-WIN32 For building on Microsoft Windows
INSTALL-LINUX For building on Linux
INSTALL-MAC For building on Apple OS X
macOS and Linux: 
Windows:
Official release builds, snapshots and development builds are all available from http://www.goldencheetah.org
NOTIO Fork
If you are looking for the NOTIO fork of GoldenCheetah it can be found here: https://github.com/notio-technologies/GCNotio