diff --git a/clippy_lints/src/large_stack_arrays.rs b/clippy_lints/src/large_stack_arrays.rs index 0acbd81ae..5857d81ab 100644 --- a/clippy_lints/src/large_stack_arrays.rs +++ b/clippy_lints/src/large_stack_arrays.rs @@ -1,7 +1,6 @@ use clippy_utils::diagnostics::span_lint_and_help; use clippy_utils::source::snippet; -use if_chain::if_chain; -use rustc_hir::{Expr, ExprKind}; +use rustc_hir::{Expr, ExprKind, Item, ItemKind, Node}; use rustc_lint::{LateContext, LateLintPass}; use rustc_middle::ty::layout::LayoutOf; use rustc_middle::ty::{self, ConstKind}; @@ -39,29 +38,28 @@ impl_lint_pass!(LargeStackArrays => [LARGE_STACK_ARRAYS]); impl<'tcx> LateLintPass<'tcx> for LargeStackArrays { fn check_expr(&mut self, cx: &LateContext<'_>, expr: &Expr<'_>) { - if_chain! { - if let ExprKind::Repeat(_, _) = expr.kind; - if let ty::Array(element_type, cst) = cx.typeck_results().expr_ty(expr).kind(); - if let ConstKind::Value(ty::ValTree::Leaf(element_count)) = cst.kind(); - if let Ok(element_count) = element_count.try_to_machine_usize(cx.tcx); - if let Ok(element_size) = cx.layout_of(*element_type).map(|l| l.size.bytes()); - if self.maximum_allowed_size < element_count * element_size; - then { - span_lint_and_help( - cx, - LARGE_STACK_ARRAYS, - expr.span, - &format!( - "allocating a local array larger than {} bytes", - self.maximum_allowed_size - ), - None, - &format!( - "consider allocating on the heap with `vec!{}.into_boxed_slice()`", - snippet(cx, expr.span, "[...]") - ), - ); - } - } + if let ExprKind::Repeat(_, _) = expr.kind + && let ty::Array(element_type, cst) = cx.typeck_results().expr_ty(expr).kind() + && let ConstKind::Value(ty::ValTree::Leaf(element_count)) = cst.kind() + && let Ok(element_count) = element_count.try_to_machine_usize(cx.tcx) + && let Ok(element_size) = cx.layout_of(*element_type).map(|l| l.size.bytes()) + && !cx.tcx.hir().parent_iter(expr.hir_id) + .any(|(_, node)| matches!(node, Node::Item(Item { kind: ItemKind::Static(..), .. }))) + && self.maximum_allowed_size < element_count * element_size { + span_lint_and_help( + cx, + LARGE_STACK_ARRAYS, + expr.span, + &format!( + "allocating a local array larger than {} bytes", + self.maximum_allowed_size + ), + None, + &format!( + "consider allocating on the heap with `vec!{}.into_boxed_slice()`", + snippet(cx, expr.span, "[...]") + ), + ); + } } } diff --git a/tests/ui/large_stack_arrays.rs b/tests/ui/large_stack_arrays.rs index d9161bfcf..6790765f8 100644 --- a/tests/ui/large_stack_arrays.rs +++ b/tests/ui/large_stack_arrays.rs @@ -12,6 +12,12 @@ enum E { T(u32), } +pub static DOESNOTLINT: [u8; 512_001] = [0; 512_001]; +pub static DOESNOTLINT2: [u8; 512_001] = { + let x = 0; + [x; 512_001] +}; + fn main() { let bad = ( [0u32; 20_000_000], diff --git a/tests/ui/large_stack_arrays.stderr b/tests/ui/large_stack_arrays.stderr index 58c0a77c1..0d91b65b4 100644 --- a/tests/ui/large_stack_arrays.stderr +++ b/tests/ui/large_stack_arrays.stderr @@ -1,5 +1,5 @@ error: allocating a local array larger than 512000 bytes - --> $DIR/large_stack_arrays.rs:17:9 + --> $DIR/large_stack_arrays.rs:23:9 | LL | [0u32; 20_000_000], | ^^^^^^^^^^^^^^^^^^ @@ -8,7 +8,7 @@ LL | [0u32; 20_000_000], = help: consider allocating on the heap with `vec![0u32; 20_000_000].into_boxed_slice()` error: allocating a local array larger than 512000 bytes - --> $DIR/large_stack_arrays.rs:18:9 + --> $DIR/large_stack_arrays.rs:24:9 | LL | [S { data: [0; 32] }; 5000], | ^^^^^^^^^^^^^^^^^^^^^^^^^^^ @@ -16,7 +16,7 @@ LL | [S { data: [0; 32] }; 5000], = help: consider allocating on the heap with `vec![S { data: [0; 32] }; 5000].into_boxed_slice()` error: allocating a local array larger than 512000 bytes - --> $DIR/large_stack_arrays.rs:19:9 + --> $DIR/large_stack_arrays.rs:25:9 | LL | [Some(""); 20_000_000], | ^^^^^^^^^^^^^^^^^^^^^^ @@ -24,7 +24,7 @@ LL | [Some(""); 20_000_000], = help: consider allocating on the heap with `vec![Some(""); 20_000_000].into_boxed_slice()` error: allocating a local array larger than 512000 bytes - --> $DIR/large_stack_arrays.rs:20:9 + --> $DIR/large_stack_arrays.rs:26:9 | LL | [E::T(0); 5000], | ^^^^^^^^^^^^^^^