如果这里最重要的方面是你希望它编译失败 if a and b是不同的类型，您可以使用 C11 的 _Generic 以及 GCC 的 __typeof__ 扩展来管理它.

If the most important aspect here is that you want it to fail to compile if a and b are different types, you can make use of C11's _Generic along with GCC's __typeof__ extension to manage this.

一个通用的例子:

#include <stdio.h>

#define TYPE_ASSERT(X,Y) _Generic ((Y), 
    __typeof__(X): _Generic ((X), 
        __typeof__(Y): (void)NULL 
    ) 
)

int main(void)
{
    int a = 1; 
    int b = 2;
    TYPE_ASSERT(a,b);
    printf("a = %d, b = %d
", a, b);
}

现在如果我们尝试编译这段代码，它会编译得很好，每个人都很高兴.

Now if we try to compile this code, it will compile fine and everybody is happy.

如果我们把b的类型改成unsigned int，但是编译会失败.

If we change the type of b to unsigned int, however, it will fail to compile.

之所以有效，是因为 _Generic 选择使用控制表达式的类型(在本例中为 (Y))来选择要遵循的规则并插入与该规则对应的代码.在这种情况下，我们只为 __typeof__(X) 提供了一个规则，因此如果 (X) 不是 (Y) 的兼容类型，没有合适的规则可供选择，因此无法编译.为了处理具有将衰减为指针的控制表达式的数组，我添加了另一个 _Generic 以另一种方式确保它们必须相互兼容，而不是接受单向兼容.而且因为——就我特别关心的——我们只想确保它在不匹配时编译失败，而不是在匹配时执行特定的操作，所以我给了相应的规则不做任何事情的任务:(void)NULL

This works because _Generic selection uses the type of a controlling expression ((Y) in this case) to select a rule to follow and insert code corresponding to the rule. In this case, we only provided a rule for __typeof__(X), thus if (X) is not a compatible type for (Y), there is no suitable rule to select and therefore cannot compile. To handle arrays, which have a controlling expression that will decay to a pointer, I added another _Generic that goes the other way ensuring they must both be compatible with one another rather than accepting one-way compatibility. And since--as far as I particularly cared--we only wanted to make sure it would fail to compile on a mismatch, rather than execute something particular upon a match, I gave the corresponding rule the task of doing nothing: (void)NULL

这种技术有一个问题:_Generic 不处理可变可修改类型，因为它是在编译时处理的.因此，如果您尝试使用可变长度数组执行此操作，它将无法编译.

There is a corner case where this technique stumbles: _Generic does not handle Variably Modifiable types since it is handled at compile time. So if you attempt to do this with a Variable Length Array, it will fail to compile.

要处理固定宽度无符号类型的特定用例，我们可以修改嵌套的 _Generic 来处理它，而不是处理数组的特殊性:

To handle your specific use-case for fixed-width unsigned types, we can modify the nested _Generic to handle that rather than handling the pecularities of an array:

#define TYPE_ASSERT(X,Y) _Generic ((Y), 
    __typeof__(X): _Generic ((Y), 
        uint8_t: (void)NULL, 
        uint16_t: (void)NULL, 
        uint32_t: (void)NULL, 
        uint64_t: (void)NULL 
   ) 
)

传递不兼容类型时的示例 GCC 错误:

Example GCC error when passing non-compatible types:

main.c: In function 'main':
main.c:7:34: error: '_Generic' selector of type 'signed char' is not compatible with any association
    7 |         __typeof__(X): _Generic ((Y), 
      |                                  ^

值得一提的是，作为 GCC 扩展的 __typeof__ 不会成为所有编译器都可移植的解决方案.不过，它似乎确实适用于 Clang，因此这是另一个支持它的主要编译器.

It is worth mentioning that __typeof__, being a GCC extension, will not be a solution that is portable to all compilers. It does seem to work with Clang, though, so that's another major compiler supporting it.