Abort in IKeyboard::updateXKBTranslationState when a virtual keyboard is created while XKB rules are unavailable (null keymap)

[chrisohearn]

Hyprland version

0.57.0 (tag v0.57.0, commit 0aa6745)

Is this a regression?

Don't know

Related: #16114 (the same unchecked null-keymap pattern in CKeybindManager::updateXKBTranslationState). This report is a different path: IKeyboard::setKeymap → IKeyboard::updateXKBTranslationState, reached when a virtual keyboard is created, with a deterministic trigger (XKB rules files missing).

What happened

Hyprland 0.57.0 aborted (SIGABRT) when a client created a zwp_virtual_keyboard_v1 at the moment the system's xkeyboard-config package was being upgraded by pacman (2.48 → 2.49). The rules files were briefly missing, so xkb_keymap_new_from_names failed and the keymap was null. Hyprland then passed it to libxkbcommon, which crashed.

Log right before the crash:

xkbcommon: ERROR: Failed to open included XKB rules "/usr/share/xkeyboard-config-2/rules/evdev"
xkbcommon: ERROR: [XKB-822] Couldn't look up rules 'evdev', model 'pc105', layout 'us', variant '', options 'omarchy:shift_caps_compose'
xkbcommon: ERROR: [XKB-822] Couldn't look up rules 'evdev', model 'pc105', layout 'us', variant '(null)', options '(null)'
Hyprland has crashed :(

Backtrace (crashing thread):

#5  xkb_keymap_num_layouts (libxkbcommon.so.0)
#6  IKeyboard::updateXKBTranslationState(xkb_keymap*)
#7  IKeyboard::setKeymap(SStringRuleNames const&)
#8  CInputManager::applyConfigToKeyboard(...)
#9  CInputManager::setupKeyboard(...)
#10 CInputManager::newVirtualKeyboard(...)
#14 CVirtualKeyboardProtocol::onCreateKeeb(...)

Expected

If the keymap cannot be compiled, keep the previous keymap or fall back to a built-in default, and log an error instead of aborting.

Steps to reproduce (inferred from the trace; not run, to avoid crashing a live session)

1. Make /usr/share/xkeyboard-config-2/rules/evdev temporarily unreadable (or upgrade xkeyboard-config during a session).
2. Create a virtual keyboard (for example, wtype a).
3. Hyprland aborts.

System

• Hyprland 0.57.0 (tag v0.57.0, commit 0aa6745), Arch Linux, kernel 7.2.14
• libxkbcommon 1.13.2, xkeyboard-config 2.49
• Note: Aquamarine was a locally patched build at the time (a display-streaming test). The crash path is entirely in input/XKB handling.

Filed by Claude Opus 5.5 via Claude Code (in T3 Code).

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