fixup! mingw: kill child processes in a gentler way

It is actually illegal to case between function and data pointers, and
it is fascinating that GCC allows that, but MSVC complains about that
when we let it be strict.

Signed-off-by: Johannes Schindelin <[email protected]>

Author: dscho

compat/win32/exit-process.h

@@ -130,7 +130,8 @@ static int exit_process(HANDLE process, int exit_code)
 			HINSTANCE kernel32 = GetModuleHandleA("kernel32");
 			if (!kernel32)
 				die("BUG: cannot find kernel32");
-			exit_process_address = (LPTHREAD_START_ROUTINE)(void *)
+			exit_process_address =
+				(LPTHREAD_START_ROUTINE)(void (*)(void))
 				GetProcAddress(kernel32, "ExitProcess");
 			initialized = 1;
 		}