[Bug 60492] New: winemac.drv: wglCreateContextAttribsARB fails for WGL_CONTEXT_OPENGL_NO_ERROR_ARB and for 3.2+ core profiles without the forward-compatible bit

[WineHQ Bugzilla]

http://bugs.winehq.org/show_bug.cgi?id=60492

            Bug ID: 60492
           Summary: winemac.drv: wglCreateContextAttribsARB fails for
                    WGL_CONTEXT_OPENGL_NO_ERROR_ARB and for 3.2+ core
                    profiles without the forward-compatible bit
           Product: Wine
           Version: 11.18
          Hardware: x86-64
                OS: MacOS
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: winemac.drv
          Assignee: [e-mail]
          Reporter: [e-mail]
  Target Milestone: ---

**Wine:** 11.18 (Gcenx build) · **macOS:** 27.0.1, M1

**Symptom:** Idle Colony (Steam 2843640) asserts `m_glContext`
(Render/Window.cpp:38) because
`wglCreateContextAttribsARB(hdc, NULL, {MAJOR 3, MINOR 3, PROFILE_MASK CORE,
0x31B3 (NO_ERROR) 0})`
returns NULL. Windows drivers (and winex11, which maps the attribute to GLX)
accept it.

Two separate refusals in `macdrv_context_create` (dlls/winemac.drv/opengl.c):
1. `WGL_CONTEXT_OPENGL_NO_ERROR_ARB` hits `default:` → "Unknown attribute",
ERROR_INVALID_PARAMETER.
   CGL has no no-error mode; the attribute is a hint (KHR_no_error allows
reporting errors anyway),
   so it can be accepted and ignored.
2. Once past that, "OS X only supports forward-compatible 3.2+ contexts": a
3.2–4.1 **core** profile
   request without WGL_CONTEXT_FORWARD_COMPATIBLE_BIT_ARB is refused. A macOS
core context is what
   the app gets either way, and Windows drivers grant it; only compatibility
profiles 3.2+ really
   can't be created.

**Patch:**
https://github.com/codeWonderland/neutron/blob/main/tools/wine-dxmt/winemac-...
(accept/ignore 0x31B3; require the FC bit only for non-core profiles).

**Repro:** `d3dprobe glcore`
(https://github.com/codeWonderland/neutron/tree/main/tools/d3dprobe) creates
exactly that context: "FAILED (error 87)" on stock 11.18 in 32- and 64-bit,
"created" (GL 4.1 Metal)
with the patch.

(Related, but a compatibility shim rather than a bug: macOS core contexts
reject GLSL `#version 130`/`140`,
which Windows core contexts compile; Dear ImGui's OpenGL3 backend uses 130.
Neutron raises them to 150
in opengl32's glShaderSource for core contexts:
tools/wine-dxmt/opengl32-glsl-version.patch.)

(Analysis and testing were done with AI assistance; the measurements are from
my own Mac. Patches are linked for reference.)

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