Update tests files for manual_dangling_ptr lint

Author: aaron-ang

tests/ui/transmute.rs

@@ -59,7 +59,7 @@ fn useless() {
         let _: *const usize = std::mem::transmute(5_isize);
         //~^ useless_transmute
 
-        let _ = 5_isize as *const usize;
+        let _ = std::ptr::dangling::<usize>();
 
         let _: *const usize = std::mem::transmute(1 + 1usize);
         //~^ useless_transmute

tests/ui/transmute_null_to_fn.rs

@@ -1,6 +1,7 @@
 #![allow(dead_code)]
 #![warn(clippy::transmute_null_to_fn)]
 #![allow(clippy::zero_ptr, clippy::missing_transmute_annotations)]
+#![allow(clippy::manual_dangling_ptr)]
 
 // Easy to lint because these only span one line.
 fn one_liners() {

tests/ui/transmute_null_to_fn.stderr

@@ -1,5 +1,5 @@
 error: transmuting a known null pointer into a function pointer
-  --> tests/ui/transmute_null_to_fn.rs:8:23
+  --> tests/ui/transmute_null_to_fn.rs:9:23
    |
 LL |         let _: fn() = std::mem::transmute(0 as *const ());
    |                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ this transmute results in undefined behavior
@@ -9,39 +9,39 @@ LL |         let _: fn() = std::mem::transmute(0 as *const ());
    = help: to override `-D warnings` add `#[allow(clippy::transmute_null_to_fn)]`
 
 error: transmuting a known null pointer into a function pointer
-  --> tests/ui/transmute_null_to_fn.rs:11:23
+  --> tests/ui/transmute_null_to_fn.rs:12:23
    |
 LL |         let _: fn() = std::mem::transmute(std::ptr::null::<()>());
    |                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ this transmute results in undefined behavior
    |
    = help: try wrapping your function pointer type in `Option<T>` instead, and using `None` as a null pointer value
 
 error: transmuting a known null pointer into a function pointer
-  --> tests/ui/transmute_null_to_fn.rs:22:23
+  --> tests/ui/transmute_null_to_fn.rs:23:23
    |
 LL |         let _: fn() = std::mem::transmute(ZPTR);
    |                       ^^^^^^^^^^^^^^^^^^^^^^^^^ this transmute results in undefined behavior
    |
    = help: try wrapping your function pointer type in `Option<T>` instead, and using `None` as a null pointer value
 
 error: transmuting a known null pointer into a function pointer
-  --> tests/ui/transmute_null_to_fn.rs:32:23
+  --> tests/ui/transmute_null_to_fn.rs:33:23
    |
 LL |         let _: fn() = std::mem::transmute(0 as *const u8 as *const ());
    |                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ this transmute results in undefined behavior
    |
    = help: try wrapping your function pointer type in `Option<T>` instead, and using `None` as a null pointer value
 
 error: transmuting a known null pointer into a function pointer
-  --> tests/ui/transmute_null_to_fn.rs:35:23
+  --> tests/ui/transmute_null_to_fn.rs:36:23
    |
 LL |         let _: fn() = std::mem::transmute(std::ptr::null::<()>() as *const u8);
    |                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ this transmute results in undefined behavior
    |
    = help: try wrapping your function pointer type in `Option<T>` instead, and using `None` as a null pointer value
 
 error: transmuting a known null pointer into a function pointer
-  --> tests/ui/transmute_null_to_fn.rs:38:23
+  --> tests/ui/transmute_null_to_fn.rs:39:23
    |
 LL |         let _: fn() = std::mem::transmute(ZPTR as *const u8);
    |                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ this transmute results in undefined behavior

tests/ui/transmuting_null.rs

@@ -3,6 +3,7 @@
 #![allow(clippy::zero_ptr)]
 #![allow(clippy::transmute_ptr_to_ref)]
 #![allow(clippy::eq_op, clippy::missing_transmute_annotations)]
+#![allow(clippy::manual_dangling_ptr)]
 
 // Easy to lint because these only span one line.
 fn one_liners() {

tests/ui/transmuting_null.stderr

@@ -1,5 +1,5 @@
 error: transmuting a known null pointer into a reference
-  --> tests/ui/transmuting_null.rs:10:23
+  --> tests/ui/transmuting_null.rs:11:23
    |
 LL |         let _: &u64 = std::mem::transmute(0 as *const u64);
    |                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -8,13 +8,13 @@ LL |         let _: &u64 = std::mem::transmute(0 as *const u64);
    = help: to override `-D warnings` add `#[allow(clippy::transmuting_null)]`
 
 error: transmuting a known null pointer into a reference
-  --> tests/ui/transmuting_null.rs:13:23
+  --> tests/ui/transmuting_null.rs:14:23
    |
 LL |         let _: &u64 = std::mem::transmute(std::ptr::null::<u64>());
    |                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: transmuting a known null pointer into a reference
-  --> tests/ui/transmuting_null.rs:24:23
+  --> tests/ui/transmuting_null.rs:25:23
    |
 LL |         let _: &u64 = std::mem::transmute(ZPTR);
    |                       ^^^^^^^^^^^^^^^^^^^^^^^^^