better error message when using NULL in to_ptr

RalfJung · RalfJung · commit e3b4f8e6c76e · 2018-08-22T13:08:39.000+02:00
diff --git a/src/librustc/mir/interpret/value.rs b/src/librustc/mir/interpret/value.rs
@@ -148,7 +148,8 @@ impl<'tcx> Scalar {
 
     pub fn to_ptr(self) -> EvalResult<'tcx, Pointer> {
         match self {
-            Scalar::Bits {..} => err!(ReadBytesAsPointer),
+            Scalar::Bits { bits: 0, .. } => err!(InvalidNullPointerUsage),
+            Scalar::Bits { .. } => err!(ReadBytesAsPointer),
             Scalar::Ptr(p) => Ok(p),
         }
     }

Original file line number	Diff line number	Diff line change
`@@ -148,7 +148,8 @@ impl<'tcx> Scalar {`
`148`	`148`
`149`	`149`	`pub fn to_ptr(self) -> EvalResult<'tcx, Pointer> {`
`150`	`150`	`match self {`
`151`		`- Scalar::Bits {..} => err!(ReadBytesAsPointer),`
	`151`	`+ Scalar::Bits { bits: 0, .. } => err!(InvalidNullPointerUsage),`
	`152`	`+ Scalar::Bits { .. } => err!(ReadBytesAsPointer),`
`152`	`153`	`Scalar::Ptr(p) => Ok(p),`
`153`	`154`	`}`
`154`	`155`	`}`