Reintroduce `Undef` and properly check constant value sizes

[rust.git] / src / librustc_mir / interpret / terminator / drop.rs

diff --git a/src/librustc_mir/interpret/terminator/drop.rs b/src/librustc_mir/interpret/terminator/drop.rs
index d750c1f47a662f5deb968d4289755e4d96f1f2d3..76aafc7121387ee1414394ebf20eb5984cbe8813 100644 (file)
--- a/src/librustc_mir/interpret/terminator/drop.rs
+++ b/src/librustc_mir/interpret/terminator/drop.rs
@@ -2,7 +2,7 @@
 use rustc::ty::{self, Ty};
 use syntax::codemap::Span;
 
-use rustc::mir::interpret::{EvalResult, Scalar, Value};
+use rustc::mir::interpret::{EvalResult, Value};
 use interpret::{Machine, ValTy, EvalContext, Place, PlaceExtra};
 
 impl<'a, 'mir, 'tcx, M: Machine<'mir, 'tcx>> EvalContext<'a, 'mir, 'tcx, M> {
@@ -33,7 +33,7 @@ pub(crate) fn drop_place(
                 ptr,
                 align: _,
                 extra: PlaceExtra::None,
-            } => ptr.to_value(),
+            } => Value::Scalar(ptr),
             _ => bug!("force_allocation broken"),
         };
         self.drop(val, instance, ty, span, target)
@@ -51,17 +51,10 @@ fn drop(
 
         let instance = match ty.sty {
             ty::TyDynamic(..) => {
-                let vtable = match arg {
-                    Value::ScalarPair(_, Scalar::Ptr(vtable)) => vtable,
-                    _ => bug!("expected fat ptr, got {:?}", arg),
-                };
-                match self.read_drop_type_from_vtable(vtable)? {
-                    Some(func) => func,
-                    // no drop fn -> bail out
-                    None => {
-                        self.goto_block(target);
-                        return Ok(())
-                    },
+                if let Value::ScalarPair(_, vtable) = arg {
+                    self.read_drop_type_from_vtable(vtable.read()?.to_ptr()?)?
+                } else {
+                    bug!("expected fat ptr, got {:?}", arg);
                 }
             }
             _ => instance,