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83 lines
2.2 KiB
Rust
83 lines
2.2 KiB
Rust
#![allow(clippy::let_unit_value)]
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fn main() {
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let x: [i32; 3] = [1_i32, 2, 3];
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let r_x = &x;
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// Check casting through multiple bindings
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// Because it's separate, it does not check the cast back to something of the same size
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let a = r_x as *const [i32];
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let b = a as *const [u8];
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let c = b as *const [u32];
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// loses data
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let loss = r_x as *const [i32] as *const [u8];
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// Cast back to same size but different type loses no data, just type conversion
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// This is weird code but there's no reason for this lint specifically to fire *twice* on it
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let restore = r_x as *const [i32] as *const [u8] as *const [u32];
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// Check casting through blocks is detected
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let loss_block_1 = { r_x as *const [i32] } as *const [u8];
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let loss_block_2 = {
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let _ = ();
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r_x as *const [i32]
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} as *const [u8];
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// Check that resores of the same size are detected through blocks
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let restore_block_1 = { r_x as *const [i32] } as *const [u8] as *const [u32];
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let restore_block_2 = { ({ r_x as *const [i32] }) as *const [u8] } as *const [u32];
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let restore_block_3 = {
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let _ = ();
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({
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let _ = ();
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r_x as *const [i32]
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}) as *const [u8]
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} as *const [u32];
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// Check that the result of a long chain of casts is detected
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let long_chain_loss = r_x as *const [i32] as *const [u32] as *const [u16] as *const [i8] as *const [u8];
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let long_chain_restore =
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r_x as *const [i32] as *const [u32] as *const [u16] as *const [i8] as *const [u8] as *const [u32];
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}
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// foo and foo2 should not fire, they're the same size
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fn foo(x: *mut [u8]) -> *mut [u8] {
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x as *mut [u8]
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}
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fn foo2(x: *mut [u8]) -> *mut [u8] {
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x as *mut _
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}
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// Test that casts as part of function returns work
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fn bar(x: *mut [u16]) -> *mut [u8] {
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x as *mut [u8]
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}
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fn uwu(x: *mut [u16]) -> *mut [u8] {
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x as *mut _
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}
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fn bar2(x: *mut [u16]) -> *mut [u8] {
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x as _
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}
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// constify
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fn bar3(x: *mut [u16]) -> *const [u8] {
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x as _
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}
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// unconstify
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fn bar4(x: *const [u16]) -> *mut [u8] {
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x as _
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}
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// function returns plus blocks
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fn blocks(x: *mut [u16]) -> *mut [u8] {
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({ x }) as _
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}
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fn more_blocks(x: *mut [u16]) -> *mut [u8] {
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{ ({ x }) as _ }
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}
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