UnsafeDestructor False Negative

[stoneman258]

Description:

I encountered an issue while testing with a slightly modified version of the test case from Rudra/tests/unsafe_destructor/normal2.rs. The issue is that Rudra does not report the UnsafeDestructor warning, even though it should.

Case

use std::ffi::CString;
use std::os::raw::c_char;

pub struct StrcCtx {
    pub ptr: *mut c_char,
}

impl Drop for StrcCtx {
    fn drop(&mut self) {
        let _ = self.to_cstring();
    }
}

impl StrcCtx {
    fn to_cstring(&mut self) -> CString {
        unsafe { std::ffi::CString::from_raw(self.ptr as *mut std::os::raw::c_char) }
    }
}

Expected Behavior:

Rudra should report an UnsafeDestructor warning for the modified test case.

Actual Behavior:

Rudra does not report any UnsafeDestructor warning.