read_c_str should call the AllocationExtra hooks

Author: RalfJung

src/librustc/mir/interpret/allocation.rs

@@ -172,10 +172,9 @@ impl<'tcx, Tag: Copy, Extra: AllocationExtra<Tag>> Allocation<Tag, Extra> {
         let offset = ptr.offset.bytes() as usize;
         match self.bytes[offset..].iter().position(|&c| c == 0) {
             Some(size) => {
-                let p1 = Size::from_bytes((size + 1) as u64);
-                self.check_relocations(cx, ptr, p1)?;
-                self.check_defined(ptr, p1)?;
-                Ok(&self.bytes[offset..offset + size])
+                let size = Size::from_bytes((size + 1) as u64);
+                // Go through `get_bytes` for checks and AllocationExtra hooks
+                self.get_bytes(cx, ptr, size)
             }
             None => err!(UnterminatedCString(ptr.erase_tag())),
         }