cpython signal handlers while creating C resources?

output.txt

 $ python test_cffi_sig.py
resources created
Traceback (most recent call last):
  File "/.../test_cffi_sig.py", line 41, in <module>
    x = using_outp()
  File "/.../test_cffi_sig.py", line 35, in using_outp
    lib.my_create_resource_outp(out)
KeyboardInterrupt
release 42

test_cffi_sig.c

#include <stdio.h>
#include <signal.h>

int my_create_resource()
{
    raise(SIGINT);
    printf("resources created\n");
    return 42;
}

void my_create_resource_outp(int* out)
{
    raise(SIGINT);
    printf("resources created\n");
    *out = 42;
}

void my_release_resource(int fd)
{
    printf("release %d\n", fd);
}

test_cffi_sig.py

from cffi import FFI

ffi = FFI()

ffi.cdef("""\
int my_create_resource();
void my_create_resource_outp(int* out);
void my_release_resource(int fd);
""")

lib = ffi.dlopen("./test_cffi_sig.so")

# x = ffi.gc(lib.my_create_resource(), lib.my_release_resource) # leaks

# also leaks
def run():
    res = None
    try:
        res = lib.my_create_resource()
    finally:
        if res is not None:
            res = ffi.gc(res, lib.my_release_resource)

class Res:
    def __init__(self, fd) -> None:
        self.fd = fd
    def __del__(self):
        lib.my_release_resource(self.fd)

# this one doesn't leak
def using_outp():
    out = ffi.new("int[1]")
    out[0] = -1
    res = None
    try:
        lib.my_create_resource_outp(out)
    finally:
        if out[0] >= 0:
            res = Res(out[0])
    return res

x = using_outp()