// Only add path to the error's import stack if it's not already present
			// in the error.
			//
			// TODO(bcmills): setLoadPackageDataError itself has a similar Push / Pop
			// sequence that empirically doesn't trigger for these errors, guarded by
			// a somewhat complex condition. Figure out how to generalize that
			// condition and eliminate the explicit calls here.
			stk.Push(path)
			defer stk.Pop()
		}