src/tools/clippy/clippy_lints/src/methods/uninit_assumed_init.rs

   1 use clippy_utils::diagnostics::span_lint;
   2 use clippy_utils::{is_expr_diagnostic_item, ty::is_uninit_value_valid_for_ty};
   3 use if_chain::if_chain;
   4 use rustc_hir as hir;
   5 use rustc_lint::LateContext;
   6 use rustc_span::sym;
   7
   8 use super::UNINIT_ASSUMED_INIT;
   9
  10 /// lint for `MaybeUninit::uninit().assume_init()` (we already have the latter)
  11 pub(super) fn check(cx: &LateContext<'_>, expr: &hir::Expr<'_>, recv: &hir::Expr<'_>) {
  12     if_chain! {
  13         if let hir::ExprKind::Call(callee, args) = recv.kind;
  14         if args.is_empty();
  15         if is_expr_diagnostic_item(cx, callee, sym::maybe_uninit_uninit);
  16         if !is_uninit_value_valid_for_ty(cx, cx.typeck_results().expr_ty_adjusted(expr));
  17         then {
  18             span_lint(
  19                 cx,
  20                 UNINIT_ASSUMED_INIT,
  21                 expr.span,
  22                 "this call for this type may be undefined behavior"
  23             );
  24         }
  25     }
  26 }