[Bug 60222] New: dxgi_output_GetDisplayModeList is a partial stub: applications that require a mode list never create a swapchain

[WineHQ Bugzilla]

http://bugs.winehq.org/show_bug.cgi?id=60222

            Bug ID: 60222
           Summary: dxgi_output_GetDisplayModeList is a partial stub:
                    applications that require a mode list never create a
                    swapchain
           Product: Wine
           Version: 11.0
          Hardware: x86-64
                OS: MacOS
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: d3d
          Assignee: [e-mail]
          Reporter: [e-mail]
  Target Milestone: ---

Created attachment 81923
  --> http://bugs.winehq.org/attachment.cgi?id=81923
+dxgi trace excerpt, game process, full call sequence

`dxgi_output_GetDisplayModeList` is a partial stub. Two application-visible
consequences follow, one fatal and one an accessibility hazard.

## 1. No swapchain is ever created

Assassin's Creed Liberation Remastered (`ACLiberation.exe`, x86_64, D3D11)
reaches its main menu — audio plays — and renders nothing: a black fullscreen
window that accepts no input, ~35% of one core, 1.6 GB resident, 51 threads,
GPU utilisation 0%.

The attached `+dxgi` excerpt is the game process's complete call sequence:
create factory, `EnumAdapters1`, `DXGID3D10CreateDevice` (feature levels 11_1
down to 9_1, device created), `EnumOutputs`, then
`dxgi_output_GetDisplayModeList` — twice per output, once with `modes NULL` for
the count and once to fill — hitting the stub every time, across three outputs,
followed by output, adapter, device and factory all released to refcount 0.

**`CreateSwapChain` is never called**, and no further DXGI activity occurs in
the minutes the process keeps running. The application then writes
`1280x720 / RefreshRate=0` into its own configuration — a fallback, not a
detection.

**Control:** `ACIII.exe` (Assassin's Creed III Remastered), a different
executable in the same directory launched the same way, runs correctly at
3440x1440. It tolerates the stub; this title requires a mode list and has no
fallback path.

## 2. Applications are handed modes the display does not have

Assassin's Creed Liberation HD, a different 32-bit D3D11 build of the same
game, does run — and its in-game resolution list offers `2560x1440@60` on a
display whose only 2560x1440 mode is 240 Hz, verified against the platform's
own mode enumeration including hidden and duplicate modes, 170 modes total.
Selecting that entry makes the application retry the mode change every frame,
producing full-screen white strobing at roughly 30–60 Hz.

The returned list is not empty, it is fictional, and applications cannot detect
that they have been misled.

## Environment

Observed under CrossOver 26.3 (`cxoffice-26.3.0rc2`, built 2026-07-15) on
macOS 26.6.2, Apple M2 Max. I have no upstream Wine build on this hardware to
retest against, so the behavioural observations come from that Wine-derived
build; the stub itself is in Wine's `dxgi` and is verifiable from source. Happy
to test a patch and report back.

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