diff --git a/clippy_lints/src/thread_local_initializer_can_be_made_const.rs b/clippy_lints/src/thread_local_initializer_can_be_made_const.rs index 9fee4c06200..2dac5ff0c3a 100644 --- a/clippy_lints/src/thread_local_initializer_can_be_made_const.rs +++ b/clippy_lints/src/thread_local_initializer_can_be_made_const.rs @@ -1,12 +1,11 @@ use clippy_config::msrvs::Msrv; use clippy_utils::diagnostics::span_lint_and_sugg; -use clippy_utils::fn_has_unsatisfiable_preds; use clippy_utils::qualify_min_const_fn::is_min_const_fn; use clippy_utils::source::snippet; +use clippy_utils::{fn_has_unsatisfiable_preds, peel_blocks}; use rustc_errors::Applicability; use rustc_hir::{intravisit, ExprKind}; -use rustc_lint::{LateContext, LateLintPass, LintContext}; -use rustc_middle::lint::in_external_macro; +use rustc_lint::{LateContext, LateLintPass}; use rustc_session::impl_lint_pass; use rustc_span::sym::thread_local_macro; @@ -57,6 +56,31 @@ impl ThreadLocalInitializerCanBeMadeConst { impl_lint_pass!(ThreadLocalInitializerCanBeMadeConst => [THREAD_LOCAL_INITIALIZER_CAN_BE_MADE_CONST]); +#[inline] +fn is_thread_local_initializer( + cx: &LateContext<'_>, + fn_kind: rustc_hir::intravisit::FnKind<'_>, + span: rustc_span::Span, +) -> Option { + let macro_def_id = span.source_callee()?.macro_def_id?; + Some( + cx.tcx.is_diagnostic_item(thread_local_macro, macro_def_id) + && matches!(fn_kind, intravisit::FnKind::ItemFn(..)), + ) +} + +#[inline] +fn initializer_can_be_made_const(cx: &LateContext<'_>, defid: rustc_span::def_id::DefId, msrv: &Msrv) -> bool { + // Building MIR for `fn`s with unsatisfiable preds results in ICE. + if !fn_has_unsatisfiable_preds(cx, defid) + && let mir = cx.tcx.optimized_mir(defid) + && let Ok(()) = is_min_const_fn(cx.tcx, mir, msrv) + { + return true; + } + false +} + impl<'tcx> LateLintPass<'tcx> for ThreadLocalInitializerCanBeMadeConst { fn check_fn( &mut self, @@ -65,31 +89,31 @@ impl<'tcx> LateLintPass<'tcx> for ThreadLocalInitializerCanBeMadeConst { _: &'tcx rustc_hir::FnDecl<'tcx>, body: &'tcx rustc_hir::Body<'tcx>, span: rustc_span::Span, - defid: rustc_span::def_id::LocalDefId, + local_defid: rustc_span::def_id::LocalDefId, ) { - if in_external_macro(cx.sess(), span) - && let Some(callee) = span.source_callee() - && let Some(macro_def_id) = callee.macro_def_id - && cx.tcx.is_diagnostic_item(thread_local_macro, macro_def_id) - && let intravisit::FnKind::ItemFn(..) = fn_kind - // Building MIR for `fn`s with unsatisfiable preds results in ICE. - && !fn_has_unsatisfiable_preds(cx, defid.to_def_id()) - && let mir = cx.tcx.optimized_mir(defid.to_def_id()) - && let Ok(()) = is_min_const_fn(cx.tcx, mir, &self.msrv) - // this is the `__init` function emitted by the `thread_local!` macro - // when the `const` keyword is not used. We avoid checking the `__init` directly - // as that is not a public API. - // we know that the function is const-qualifiable, so now we need only to get the - // initializer expression to span-lint it. + let defid = local_defid.to_def_id(); + if is_thread_local_initializer(cx, fn_kind, span).unwrap_or(false) + // Some implementations of `thread_local!` include an initializer fn. + // In the case of a const initializer, the init fn is also const, + // so we can skip the lint in that case. This occurs only on some + // backends due to conditional compilation: + // https://doc.rust-lang.org/src/std/sys/common/thread_local/mod.rs.html + // for details on this issue, see: + // https://github.com/rust-lang/rust-clippy/pull/12276 + && !cx.tcx.is_const_fn(defid) + && initializer_can_be_made_const(cx, defid, &self.msrv) + // we know that the function is const-qualifiable, so now + // we need only to get the initializer expression to span-lint it. && let ExprKind::Block(block, _) = body.value.kind - && let Some(ret_expr) = block.expr + && let Some(unpeeled) = block.expr + && let ret_expr = peel_blocks(unpeeled) && let initializer_snippet = snippet(cx, ret_expr.span, "thread_local! { ... }") && initializer_snippet != "thread_local! { ... }" { span_lint_and_sugg( cx, THREAD_LOCAL_INITIALIZER_CAN_BE_MADE_CONST, - ret_expr.span, + unpeeled.span, "initializer for `thread_local` value can be made `const`", "replace with", format!("const {{ {initializer_snippet} }}"), diff --git a/tests/ui/thread_local_initializer_can_be_made_const.fixed b/tests/ui/thread_local_initializer_can_be_made_const.fixed index bbde25b0a88..1a2c5ffc56f 100644 --- a/tests/ui/thread_local_initializer_can_be_made_const.fixed +++ b/tests/ui/thread_local_initializer_can_be_made_const.fixed @@ -27,4 +27,11 @@ fn main() { } //~^^^^ ERROR: initializer for `thread_local` value can be made `const` //~^^^ ERROR: initializer for `thread_local` value can be made `const` + + thread_local! { + static PEEL_ME: i32 = const { 1 }; + //~^ ERROR: initializer for `thread_local` value can be made `const` + static PEEL_ME_MANY: i32 = const { { let x = 1; x * x } }; + //~^ ERROR: initializer for `thread_local` value can be made `const` + } } diff --git a/tests/ui/thread_local_initializer_can_be_made_const.rs b/tests/ui/thread_local_initializer_can_be_made_const.rs index 3d7aacf2f09..7fb00cd1342 100644 --- a/tests/ui/thread_local_initializer_can_be_made_const.rs +++ b/tests/ui/thread_local_initializer_can_be_made_const.rs @@ -27,4 +27,11 @@ fn main() { } //~^^^^ ERROR: initializer for `thread_local` value can be made `const` //~^^^ ERROR: initializer for `thread_local` value can be made `const` + + thread_local! { + static PEEL_ME: i32 = { 1 }; + //~^ ERROR: initializer for `thread_local` value can be made `const` + static PEEL_ME_MANY: i32 = { let x = 1; x * x }; + //~^ ERROR: initializer for `thread_local` value can be made `const` + } } diff --git a/tests/ui/thread_local_initializer_can_be_made_const.stderr b/tests/ui/thread_local_initializer_can_be_made_const.stderr index 9ee52fbbb31..b4f8bd822b0 100644 --- a/tests/ui/thread_local_initializer_can_be_made_const.stderr +++ b/tests/ui/thread_local_initializer_can_be_made_const.stderr @@ -25,5 +25,17 @@ error: initializer for `thread_local` value can be made `const` LL | static BUF_4_CAN_BE_MADE_CONST: RefCell = RefCell::new(String::new()); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: replace with: `const { RefCell::new(String::new()) }` -error: aborting due to 4 previous errors +error: initializer for `thread_local` value can be made `const` + --> tests/ui/thread_local_initializer_can_be_made_const.rs:32:31 + | +LL | static PEEL_ME: i32 = { 1 }; + | ^^^^^ help: replace with: `const { 1 }` + +error: initializer for `thread_local` value can be made `const` + --> tests/ui/thread_local_initializer_can_be_made_const.rs:34:36 + | +LL | static PEEL_ME_MANY: i32 = { let x = 1; x * x }; + | ^^^^^^^^^^^^^^^^^^^^ help: replace with: `const { { let x = 1; x * x } }` + +error: aborting due to 6 previous errors