你需要扩展你的sass.config.js文件，默认情况下为sass提供源映射被禁用。

You'll need to extend your sass.config.js file, by default source mapping for sass is disabled.

config / sass.config.js：

config/sass.config.js:

module.exports = {
  sourceMap: true,
}

package.json ：

package.json:

"config": {
  "ionic_sass": "./config/sass.config.js",
},

https://github.com/GerritErpenstein/ionic2-custom-icons/blob/master/docs/CONFIGURATION.md

干杯，