为什么调用 SetConsoleCtrlHandler() 会触发警告？

Question

#include <windows.h>

BOOL MyCtrlHandler(DWORD ctrlType) {
    return TRUE;
}

int main(void) {
    SetConsoleCtrlHandler(MyCtrlHandler, TRUE);
    return 0;
}

函数签名匹配 doc:

The PHANDLER_ROUTINE type defines a pointer to this callback function. HandlerRoutine is a placeholder for the application-defined function name.

如果我用 64 位的 MinGW 交叉编译它，它可以工作：

$ x86_64-w64-mingw32-gcc ctrl.c
$

但是在 32 位中，我收到警告：

$ i686-w64-mingw32-gcc ctrl.c
ctrl.c: In function ‘main’:
ctrl.c:8:27: warning: passing argument 1 of ‘SetConsoleCtrlHandler’ from incompatible pointer type [-Wincompatible-pointer-types]
    8 |     SetConsoleCtrlHandler(MyCtrlHandler, TRUE);
      |                           ^~~~~~~~~~~~~
      |                           |
      |                           BOOL (*)(DWORD) {aka int (*)(long unsigned int)}
In file included from /usr/share/mingw-w64/include/windows.h:74,
                 from ctrl.c:1:
/usr/share/mingw-w64/include/wincon.h:249:68: note: expected ‘PHANDLER_ROUTINE’ but argument is of type ‘BOOL (*)(DWORD)’ {aka ‘int (*)(long unsigned int)’}
  249 |   WINBASEAPI WINBOOL WINAPI SetConsoleCtrlHandler(PHANDLER_ROUTINE HandlerRoutine,WINBOOL Add);
      |
$

我不明白为什么，因为MyCtrlHandler应该和PHANDLER_ROUTINE有相同的类型。

Answer 1

这里的问题是__cdecl和__stdcall的区别。在一次成功的编译尝试中，您一定很幸运地使用了默认调用约定。您需要：

BOOL WINAPI MyCtrlHandler(DWORD ctrlType) {
    return TRUE;
}

为什么调用 SetConsoleCtrlHandler() 会触发警告？

Why calling SetConsoleCtrlHandler() triggers a warning?

c

windows

mingw

compiler-warnings