comment

Co-authored-by: Oli Scherer <[email protected]>

Author: RalfJung

compiler/rustc_codegen_ssa/src/mir/rvalue.rs

@@ -270,6 +270,9 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                         PointerCast::MutToConstPointer | PointerCast::ArrayToPointer,
                     )
                     | mir::CastKind::Misc
+                    // Since int2ptr can have arbitrary integer types as input (so we have to do
+                    // sign extension and all that), it is currently best handled in the same code
+                    // path as the other integer-to-X casts.
                     | mir::CastKind::PointerFromExposedAddress => {
                         assert!(bx.cx().is_backend_immediate(cast));
                         let ll_t_out = bx.cx().immediate_backend_type(cast);

compiler/rustc_const_eval/src/transform/promote_consts.rs

@@ -504,7 +504,7 @@ impl<'tcx> Validator<'_, 'tcx> {
             // ptr-to-int casts are not possible in consts and thus not promotable
             Rvalue::Cast(CastKind::PointerExposeAddress, _, _) => return Err(Unpromotable),
 
-            // all ohter casts including int-to-ptr casts are fine, they just use the integer value
+            // all other casts including int-to-ptr casts are fine, they just use the integer value
             // at pointer type.
             Rvalue::Cast(_, operand, _) => {
                 self.validate_operand(operand)?;