diff --git a/src/citra_qt/debugger/graphics_framebuffer.cpp b/src/citra_qt/debugger/graphics_framebuffer.cpp
index c30e75933aa04f78efefd59f886d967f81dd4988..68cff78b21a7f81c6ad1962b29a08ab2130668b3 100644
--- a/src/citra_qt/debugger/graphics_framebuffer.cpp
+++ b/src/citra_qt/debugger/graphics_framebuffer.cpp
@@ -346,5 +346,11 @@ u32 GraphicsFramebufferWidget::BytesPerPixel(GraphicsFramebufferWidget::Format f
         case Format::RGBA4:
         case Format::D16:
             return 2;
+        default:
+            UNREACHABLE_MSG("GraphicsFramebufferWidget::BytesPerPixel: this "
+                            "should not be reached as this function should "
+                            "be given a format which is in "
+                            "GraphicsFramebufferWidget::Format. Instead got %i",
+                            static_cast<int>(format));
     }
 }