Under mingw64:
../signal.c:88:0: warning: "__cdecl" redefined
#define __cdecl
<built-in>: note: this is the location of the previous definition
https://ci.appveyor.com/project/azat/libevent/builds/
23321613#L427
(cherry picked from commit
b8e2f01690c07f7b6eb29d097b30c1640fc9612e)
#ifndef _WIN32
/* Windows wants us to call our signal handlers as __cdecl. Nobody else
* expects you to do anything crazy like this. */
+#ifndef __cdecl
#define __cdecl
#endif
+#endif
static int evsig_add(struct event_base *, evutil_socket_t, short, short, void *);
static int evsig_del(struct event_base *, evutil_socket_t, short, short, void *);