--- /dev/null
+use super::utils::get_type_snippet;
+use super::TRANSMUTE_PTR_TO_REF;
+use crate::utils::{span_lint_and_then, sugg};
+use rustc_errors::Applicability;
+use rustc_hir::{Expr, Mutability, QPath};
+use rustc_lint::LateContext;
+use rustc_middle::ty::{self, Ty};
+
+/// Checks for `transmute_ptr_to_ref` lint.
+/// Returns `true` if it's triggered, otherwise returns `false`.
+pub(super) fn check<'tcx>(
+ cx: &LateContext<'tcx>,
+ e: &'tcx Expr<'_>,
+ from_ty: Ty<'tcx>,
+ to_ty: Ty<'tcx>,
+ args: &'tcx [Expr<'_>],
+ qpath: &'tcx QPath<'_>,
+) -> bool {
+ match (&from_ty.kind(), &to_ty.kind()) {
+ (ty::RawPtr(from_ptr_ty), ty::Ref(_, to_ref_ty, mutbl)) => {
+ span_lint_and_then(
+ cx,
+ TRANSMUTE_PTR_TO_REF,
+ e.span,
+ &format!(
+ "transmute from a pointer type (`{}`) to a reference type (`{}`)",
+ from_ty, to_ty
+ ),
+ |diag| {
+ let arg = sugg::Sugg::hir(cx, &args[0], "..");
+ let (deref, cast) = if *mutbl == Mutability::Mut {
+ ("&mut *", "*mut")
+ } else {
+ ("&*", "*const")
+ };
+
+ let arg = if from_ptr_ty.ty == *to_ref_ty {
+ arg
+ } else {
+ arg.as_ty(&format!("{} {}", cast, get_type_snippet(cx, qpath, to_ref_ty)))
+ };
+
+ diag.span_suggestion(
+ e.span,
+ "try",
+ sugg::make_unop(deref, arg).to_string(),
+ Applicability::Unspecified,
+ );
+ },
+ );
+ true
+ },
+ _ => false,
+ }
+}