user0/rust
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Auto merge of #12010 - granddaifuku:fix/manual-memcpy-indexing-for-multi-dimension-arrays, r=Alexendoo

Browse source 
fix: `manual_memcpy` wrong indexing for multi dimensional arrays

fixes: #9334

This PR fixes an invalid suggestion for multi-dimensional arrays.

For example,
```rust
let src = vec![vec![0; 5]; 5];
let mut dst = vec![0; 5];

for i in 0..5 {
    dst[i] = src[i][i];
}
```

For the above code, Clippy suggests `dst.copy_from_slice(&src[i]);`, but it is not compilable because `i` is only used to loop the array.
I adjusted it so that Clippy `manual_memcpy` works properly for multi-dimensional arrays.

changelog: [`manual_memcpy`]: Fixes invalid indexing suggestions for multi-dimensional arrays
This commit is contained in:
bors 2024-03-01 12:05:03 +00:00
commit e865dca4d7
3 changed files with 79 additions and 6 deletions
Download patch file Download diff file Expand all files Collapse all files

6
clippy_lints/src/loops/manual_memcpy.rs
View file

@ -3,6 +3,7 @@ use clippy_utils::diagnostics::span_lint_and_sugg;
use clippy_utils::source::snippet;
use clippy_utils::sugg::Sugg;
use clippy_utils::ty::is_copy;
use clippy_utils::usage::local_used_in;
use clippy_utils::{get_enclosing_block, higher, path_to_local, sugg};
use rustc_ast::ast;
use rustc_errors::Applicability;
@ -63,8 +64,9 @@ pub(super) fn check<'tcx>(
&& get_slice_like_element_ty(cx, cx.typeck_results().expr_ty(base_right)).is_some()
&& let Some((start_left, offset_left)) = get_details_from_idx(cx, idx_left, &starts)
&& let Some((start_right, offset_right)) = get_details_from_idx(cx, idx_right, &starts)
// Source and destination must be different
&& !local_used_in(cx, canonical_id, base_left)
&& !local_used_in(cx, canonical_id, base_right)
// Source and destination must be different
&& path_to_local(base_left) != path_to_local(base_right)
{
Some((