别人提供了下载办法，吾找到了修改脚本的解决办法。
- 下载文件
git clone https://github.com/quantum6/xcode-missing-libstdcpp
- 修改脚本（独家办法）
#!/usr/bin/env bash
set -e
DEST_DIR=/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk/usr
sudo ln -snf \
$PWD/include/c++ \
${DEST_DIR}/include/
sudo ln -snf \
$PWD/lib/libstdc++.6.0.9.tbd \
$PWD/lib/libstdc++.6.tbd \
$PWD/lib/libstdc++.tbd \
${DEST_DIR}/lib/
- 安装
./install.sh
- 配置环境
NEW_INCLUDE=/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/include/c++/v1
export CFLAGS="-I$NEW_INCLUDE"
export CXXFLAGS="-I$NEW_INCLUDE"
NEW_LIB=/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk/usr/lib
export LDFLAGS="-L${NEW_LIB}"
export LIBRARY_PATH=$NEW_LIB:$LIBRARY_PATH
