unresolved external symbol PyExc_RuntimeError

Below is the cause of the unresolved symbol. I tried inserting `__declspec(dllimport)` but clang complains that the assignment to `_cgohack_PyExc_RuntimeError ` is not a constant expression. It seemed to build and link without a problem if I commented the two lines out. I don't understand what the intent is here.
```c
extern char PyExc_RuntimeError[];
void *_cgohack_PyExc_RuntimeError = PyExc_RuntimeError;
```

未指定文件、测试或入口点。首先追踪所示 C 声明的生成位置以及 CPython 扩展的链接方式，然后在受影响的 toolchain 上复现未解析的 PyExc_RuntimeError 符号。完成标准是：不注释掉这些行即可构建并链接该扩展，并且由适当的 build 或 link check 覆盖该行为。

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