Installing `dulwich` gives `error: command 'clang' failed with exit status 1`

Question

当我尝试执行 pip install dulwich 时，我最终看到一堵红色的墙抱怨 clang。这是最后一点：

    Please check your Xcode installation
    clang -Wno-unused-result -Wsign-compare -Wunreachable-code -fno-common -dynamic -DNDEBUG -g -fwrapv -O3 -Wall -isysroot /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.14.sdk -I/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.14.sdk/usr/include -I/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.14.sdk/System/Library/Frameworks/Tk.framework/Versions/8.5/Headers -I/usr/local/include -I/usr/local/opt/openssl/include -I/usr/local/opt/openssl/include -I/usr/local/include -I/usr/local/opt/openssl@1.1/include -I/usr/local/opt/sqlite/include -I/Users/alaird/Developer/py3venv/include -I/usr/local/Cellar/python/3.7.4_1/Frameworks/Python.framework/Versions/3.7/include/python3.7m -c dulwich/_objects.c -o build/temp.macosx-10.14-x86_64-3.7/dulwich/_objects.o
    clang: warning: no such sysroot directory: '/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.14.sdk' [-Wmissing-sysroot]
    In file included from dulwich/_objects.c:20:
    /usr/local/Cellar/python/3.7.4_1/Frameworks/Python.framework/Versions/3.7/include/python3.7m/Python.h:25:10: fatal error: 'stdio.h' file not found
    #include <stdio.h>
             ^~~~~~~~~
    1 error generated.
    error: command 'clang' failed with exit status 1
    ----------------------------------------
ERROR: Command "/Users/alaird/Developer/py3venv/bin/python -u -c 'import setuptools, tokenize;__file__='"'"'/private/var/folders/63/r_rf7mhj14b4c42mfkkl06t8rg1b1r/T/pip-install-b9wlh7xh/dulwich/setup.py'"'"';f=getattr(tokenize, '"'"'open'"'"', open)(__file__);code=f.read().replace('"'"'\r\n'"'"', '"'"'\n'"'"');f.close();exec(compile(code, __file__, '"'"'exec'"'"'))' install --record /private/var/folders/63/r_rf7mhj14b4c42mfkkl06t8rg1b1r/T/pip-record-_v0dq_sp/install-record.txt --single-version-externally-managed --compile --install-headers /Users/alaird/Developer/py3venv/include/site/python3.7/dulwich" failed with error code 1 in /private/var/folders/63/r_rf7mhj14b4c42mfkkl06t8rg1b1r/T/pip-install-b9wlh7xh/dulwich/

我在 Google 上写了很多“clang 失败，退出状态为 1”的兔子洞，问题是这太笼统了。回答几个问题：

是的，Xcode 是最新版本，并且已经安装了命令行工具（我在 OS X 10.14.6，所以现在通过应用程序更新进行管理）。
这是一个以前工作的安装。在我执行 make clean 后开始出现此错误，这使我的 venv.
尝试安装最新的 setuptools 会遇到同样的错误，所以感觉指向 Xcode/my 构建环境（而不是 dulwich）的错误才是正确的罪魁祸首。
做 brew update 也给我同样的 clang 呕吐。当我升级到 Mojave 时，我觉得有些东西被清理了。

想法？

Answer 1

啊哈！

我开始查看警告而不是错误：

no such sysroot directory: '/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.14.sdk' [-Wmissing-sysroot]

这让我注意到 SDK 版本号是硬编码的……这看起来很愚蠢。所以我建立了一个符号链接：

ln -s /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk/ /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.14.sdk

根据您的系统配置，您可能需要构建不同的符号链接（还有一个 MacOSX10.15.sdk 文件夹）。

然后成功了！ pip 没有问题（包括安装 dulwich 和 pycrypto），brew 没有问题，我的开发环境一切正常！

我也做了：

export CFLAGS="-isysroot /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk"

但是，我不认为这是什么原因造成的，因为在开始新的会话后一切仍然有效。所以可能是上面的符号链接解决了它。希望这对其他人有帮助！

Installing `dulwich` gives `error: command 'clang' failed with exit status 1`

Installing `dulwich` gives `error: command 'clang' failed with exit status 1`

python

clang

macos-mojave