fyne-io/fyne · error

eglSwapBuffer failed\n

Error message

eglSwapBuffer failed\n

What it means

Unlike the other x11.c failures, this one fires during the render loop: swapBuffers() calls eglSwapBuffers each frame and exits(1) with 'eglSwapBuffer failed' (the message misspells eglSwapBuffers) when the swap returns EGL_FALSE. That means the surface is no longer swap-able: the window/surface was destroyed, the EGL context was lost (GPU reset, suspend/resume), or the display connection dropped mid-run.

Source

Thrown at internal/driver/mobile/app/x11.c:172

			onTouchMove((float)ev.xmotion.x, (float)ev.xmotion.y);
			break;
		case ConfigureNotify:
			onResize(ev.xconfigure.width, ev.xconfigure.height);
			break;
		case ClientMessage:
			if (wm_delete_window != None && (Atom)ev.xclient.data.l[0] == wm_delete_window) {
				onStop();
				return;
			}
			break;
		}
	}
}

void
swapBuffers(void) {
	if (eglSwapBuffers(e_dpy, e_surf) == EGL_FALSE) {
		fprintf(stderr, "eglSwapBuffer failed\n");
		exit(1);
	}
}

View on GitHub (pinned to 8860ee95c3)

Solutions

1. Restart the application after GPU/driver resets or suspend/resume cycles; the process exits immediately by design
2. Keep the display connection and window alive for the whole render loop; do not destroy the window from another goroutine/thread mid-swap
3. Update Mesa/GPU drivers to reduce spurious context loss
4. If you build the driver, replace exit(1) with an eglMakeCurrent retry or surface recreation on EGL_CONTEXT_LOST

Example fix

// before (x11.c): any failed swap kills the process
void
swapBuffers(void) {
	if (eglSwapBuffers(e_dpy, e_surf) == EGL_FALSE) {
		fprintf(stderr, "eglSwapBuffer failed\n");
		exit(1);
	}
}

// after: attempt recovery once before giving up
void
swapBuffers(void) {
	if (eglSwapBuffers(e_dpy, e_surf) == EGL_FALSE) {
		if (eglGetError() == EGL_CONTEXT_LOST && eglMakeCurrent(e_dpy, e_surf, e_surf, e_ctx))
			return;
		fprintf(stderr, "eglSwapBuffer failed\n");
		exit(1);
	}
}

func swapPreflight(w fyne.Window) error {
	if w == nil || w.Canvas() == nil {
		return fmt.Errorf("window/canvas destroyed; cannot swap buffers")
	}
	return nil
}

When it happens

Trigger: Calling swapBuffers() after the window has been closed/destroyed, after a driver/GPU reset invalidates the context, or while the X display connection is being torn down (session ending, SSH dropping).

Common situations: Laptop suspend/resume under the app; closing the window while a frame swap is in flight; driver crashes/recovery (TDR); long-running kiosk apps across display restarts.

Related errors

• eglChooseConfig failed\n
• eglGetConfigAttrib failed\n
• XGetVisualInfo failed\n
• eglCreateWindowSurface failed\n
• eglGetDisplay failed\n

AI-assisted analysis of fyne-io/fyne@8860ee95c3 (2026-08-15). Data as JSON: /api/errors/d8f3e1c7c696c1e6. Report an issue: GitHub.