Binding the right and left analog to the same binds breaks the inputs.

Is there an existing issue for this?

• This is a bug in RetroArch frontend
• I have searched the existing issues

Description

Title, I've tested this on both melonDS and melonDS DS. First tested alternating both joysticks on the xinput controller driver. It'll prioritise one of the two joysticks, and the other would be locked to only vertical or horizontal movement. If you fiddle with the controls it'll change the joystick and the right one would work, instead of the left one. After changing the driver to SDL2 and still having the same controls bound does the same thing, except for some reason it changed the right analog stick to inverted controls. Even when it's bugged out doing only vertical or horizontal, and the left analog stick doesn't do inverted controls.

Expected behavior

I expected the controls the freak out while using them simultaneously, but not when using them while alternating.

Steps to reproduce the bug

1. Menu > Quick Menu > Controls
2. Bind the left joystick correctly
3. Do the same for the right joystick
4. Menu > Quick Menu > Core Options > Screen
5. Set touch mode to joystick
6. Close out the menu and go into game
7. Move joysticks

Version/Commit

1.20.0 (git e4fe551)

Bisect Results

Not sure

Present in the nightly version

I don't know

Platform & operating system

Windows 11 23H2

Affected Cores

melonDS 0.9.3 7a3c11f, melonDS DS 1.1.8

Environment information

Affected controller drivers: sdl2, xinput
i7 9700k
nVidia 3060 12gb
32g ddr4 RAM
64bit operating system, x64 processor

Relevant log output

[retroarch__2025_02_19__16_31_23.log](https://github.com/user-attachments/files/18871039/retroarch__2025_02_19__16_31_23.log)

Start by reproducing the issue through Quick Menu > Controls and Core Options > Screen with the xinput and SDL2 controller drivers, using the listed melonDS cores. Confirm whether alternating the left and right analog sticks causes axis locking or inversion, and consider the issue resolved when both sticks retain their intended bindings during alternating use.