For SDL2 game controller support, at least SDL 2.0.4 is required.
Under the assets directory is the SDL2 game controller database: gamecontrollerdb.txt. This file contains many known control pad mappings for Windows, Linux and MAC OS. PPSSPPSDL will load this file at start-up and work out how to assign control pad buttons for your control pad.
Hot plugging of control pads is also supported.
If you control pad has a "Guide" or "Home" button then when pressed, this will trigger the emulator pause menu, thus allowing you to exit the emulator if you wish or load another game from your library.
Here's an example where we both use suppressions, and generate new ones (that you can then take from suppressions.log and simplify and copy to valgrind-wsl2.supp):