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// check-pass
struct MyStruct {
field: bool,
inner_array: [char; 1],
raw_ptr: *mut u8
}
impl MyStruct {
fn use_mut(&mut self) {}
}
struct Mutable {
msg: &'static str,
}
impl Drop for Mutable {
fn drop(&mut self) {
println!("{}", self.msg);
}
}
struct Mutable2 { // this one has drop glue but not a Drop impl
msg: &'static str,
other: String,
}
const ARRAY: [u8; 1] = [25];
const MY_STRUCT: MyStruct = MyStruct { field: true, inner_array: ['a'], raw_ptr: 2 as *mut u8 };
const RAW_PTR: *mut u8 = 1 as *mut u8;
const MUTABLE: Mutable = Mutable { msg: "" };
const MUTABLE2: Mutable2 = Mutable2 { msg: "", other: String::new() };
const VEC: Vec<i32> = Vec::new();
const PTR: *mut () = 1 as *mut _;
const PTR_TO_ARRAY: *mut [u32; 4] = 0x12345678 as _;
const ARRAY_OF_PTR: [*mut u32; 1] = [1 as *mut _];
fn main() {
ARRAY[0] = 5; //~ WARN attempting to modify
MY_STRUCT.field = false; //~ WARN attempting to modify
MY_STRUCT.inner_array[0] = 'b'; //~ WARN attempting to modify
MY_STRUCT.use_mut(); //~ WARN taking
&mut MY_STRUCT; //~ WARN taking
(&mut MY_STRUCT).use_mut(); //~ WARN taking
// Test that we don't warn when writing through
// a raw pointer
// This is U.B., but this test is check-pass,
// so this never actually executes
unsafe {
*RAW_PTR = 0;
*MY_STRUCT.raw_ptr = 0;
}
MUTABLE.msg = "wow"; // no warning, because Drop observes the mutation
MUTABLE2.msg = "wow"; //~ WARN attempting to modify
VEC.push(0); //~ WARN taking a mutable reference to a `const` item
// Test that we don't warn when converting a raw pointer
// into a mutable reference
unsafe { &mut *PTR };
// Test that we don't warn when there's a dereference involved.
// If we ever 'leave' the const via a deference, we're going
// to end up modifying something other than the temporary
unsafe { (*PTR_TO_ARRAY)[0] = 1 };
unsafe { *ARRAY_OF_PTR[0] = 25; }
}
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