Swift po 导致错误“无法加载链接库 Metal”

使用Swift进行开发时，有时候在使用"po"命令打印调试信息时，可能会遇到一个错误提示："无法加载链接库Metal"。这个错误通常会出现在使用Metal图形库进行图形渲染的项目中。在本文中，我们将讨论这个错误的原因，并提供一些解决方案。

swift
import Metal
// 检查设备的兼容性
guard let device = MTLCreateSystemDefaultDevice() else {
    print("设备不支持Metal")
    return
}
// 创建Metal渲染管道
let defaultLibrary = device.makeDefaultLibrary()
let pipelineDescriptor = MTLRenderPipelineDescriptor()
pipelineDescriptor.vertexFunction = defaultLibrary?.makeFunction(name: "vertexShader")
pipelineDescriptor.fragmentFunction = defaultLibrary?.makeFunction(name: "fragmentShader")
pipelineDescriptor.colorAttachments[0].pixelFormat = .bgra8Unorm
do {
    let pipelineState = try device.makeRenderPipelineState(descriptor: pipelineDescriptor)
    
    // 执行渲染操作
    let commandQueue = device.makeCommandQueue()
    let commandBuffer = commandQueue?.makeCommandBuffer()
    let renderPassDescriptor = MTLRenderPassDescriptor()
    let drawable = view.currentDrawable
    
    // 设置渲染目标和清除颜色
    renderPassDescriptor.colorAttachments[0].texture = drawable?.texture
    renderPassDescriptor.colorAttachments[0].loadAction = .clear
    renderPassDescriptor.colorAttachments[0].clearColor = MTLClearColor(red: 0, green: 0, blue: 0, alpha: 1)
    
    let renderEncoder = commandBuffer?.makeRenderCommandEncoder(descriptor: renderPassDescriptor)
    renderEncoder?.setRenderPipelineState(pipelineState)
    
    // 执行渲染操作
    
    renderEncoder?.endEncoding()
    commandBuffer?.present(drawable!)
    commandBuffer?.commit()
} catch {
    print("创建渲染管道失败：\(error)")
}