fyne-io/fyne · critical

eglCreateContext failed\n

Error message

eglCreateContext failed\n

What it means

x11.c requests an OpenGL ES 2 client context (EGL_CONTEXT_CLIENT_VERSION 2) with eglCreateContext. Failure means the EGL implementation could not provide a GLES2 context on this display: no GLES2 runtime present, a desktop-GL-only EGL (typical of older proprietary drivers), or a driver/config mismatch. The process prints 'eglCreateContext failed' and exits(1).

Source

Thrown at internal/driver/mobile/app/x11.c:80

	Window win = XCreateWindow(
		x_dpy, root, 0, 0, w, h, 0, visInfo->depth, InputOutput,
		visInfo->visual, CWColormap | CWEventMask, &attr);
	XFree(visInfo);

	XSizeHints sizehints;
	sizehints.width  = w;
	sizehints.height = h;
	sizehints.flags = USSize;
	XSetNormalHints(x_dpy, win, &sizehints);
	XSetStandardProperties(x_dpy, win, "App", "App", None, (char **)NULL, 0, &sizehints);

	static const EGLint ctx_attribs[] = {
		EGL_CONTEXT_CLIENT_VERSION, 2,
		EGL_NONE
	};
	*ctx = eglCreateContext(e_dpy, config, EGL_NO_CONTEXT, ctx_attribs);
	if (!*ctx) {
		fprintf(stderr, "eglCreateContext failed\n");
		exit(1);
	}
	*surf = eglCreateWindowSurface(e_dpy, config, win, NULL);
	if (!*surf) {
		fprintf(stderr, "eglCreateWindowSurface failed\n");
		exit(1);
	}
	return win;
}

Display *x_dpy;
EGLDisplay e_dpy;
EGLContext e_ctx;
EGLSurface e_surf;
Window win;

void
createWindow(void) {

View on GitHub (pinned to 8860ee95c3)

Solutions

1. Install the GLES2 runtime: apt install libgles2 libgl1-mesa-dri libegl-mesa0
2. Force Mesa software GLES: LIBGL_ALWAYS_SOFTWARE=1 ./yourapp
3. Verify which client APIs EGL offers: eglinfo should list OpenGL ES 2.x
4. Update the proprietary driver if on NVIDIA/AMD stacks lacking EGL GLES entries
5. Set EGL_PLATFORM=x11 so the correct platform display is initialized

Example fix

# before: EGL has config but no GLES2 client API -> exit(1)
./yourapp  # eglCreateContext failed

# after: install GLES runtime and fall back to software if needed
sudo apt install libgles2 libegl-mesa0 mesa-utils
eglinfo | grep -i 'client api'
LIBGL_ALWAYS_SOFTWARE=1 ./yourapp

func glesPreflight() error {
	out, err := exec.Command("sh", "-c", "eglinfo | grep -i 'client api'").CombinedOutput()
	if err != nil || !bytes.Contains(out, []byte("OpenGL ES")) {
		return fmt.Errorf("EGL lacks a GLES client API; install libgles2 libegl-mesa0 or set LIBGL_ALWAYS_SOFTWARE=1")
	}
	return nil
}

When it happens

Trigger: eglCreateContext returning EGL_NO_CONTEXT after a valid config was chosen: missing libGLESv2/GLES2 support in Mesa, NVIDIA's EGL historically exposing only desktop GL client APIs, or a broken GLES loader.

Common situations: Containers or minimal installs without the libgles2 package; machines with proprietary drivers lacking GLES; mixed Mesa/NVIDIA ICD setups where eglChooseConfig succeeded against the wrong vendor.

Related errors

• eglGetConfigAttrib failed\n
• eglChooseConfig failed\n
• eglGetDisplay failed\n
• eglInitialize failed\n
• eglMakeCurrent failed\n

AI-assisted analysis of fyne-io/fyne@8860ee95c3 (2026-08-15). Data as JSON: /api/errors/58b1d26f1795a2b4. Report an issue: GitHub.