make MPlaceTy non-Copy

Author: RalfJung

src/helpers.rs

@@ -600,14 +600,14 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     /// necessary.
     fn last_error_place(&mut self) -> InterpResult<'tcx, MPlaceTy<'tcx, Provenance>> {
         let this = self.eval_context_mut();
-        if let Some(errno_place) = this.active_thread_ref().last_error {
-            Ok(errno_place)
+        if let Some(errno_place) = this.active_thread_ref().last_error.as_ref() {
+            Ok(errno_place.clone())
         } else {
             // Allocate new place, set initial value to 0.
             let errno_layout = this.machine.layouts.u32;
             let errno_place = this.allocate(errno_layout, MiriMemoryKind::Machine.into())?;
             this.write_scalar(Scalar::from_u32(0), &errno_place)?;
-            this.active_thread_mut().last_error = Some(errno_place);
+            this.active_thread_mut().last_error = Some(errno_place.clone());
             Ok(errno_place)
         }
     }
@@ -725,7 +725,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
 
         let mplace = MPlaceTy::from_aligned_ptr(ptr, layout);
 
-        this.check_mplace(mplace)?;
+        this.check_mplace(&mplace)?;
 
         Ok(mplace)
     }

src/machine.rs

@@ -668,7 +668,7 @@ impl<'mir, 'tcx> MiriMachine<'mir, 'tcx> {
                 Self::add_extern_static(
                     this,
                     "environ",
-                    this.machine.env_vars.environ.unwrap().ptr,
+                    this.machine.env_vars.environ.as_ref().unwrap().ptr,
                 );
                 // A couple zero-initialized pointer-sized extern statics.
                 // Most of them are for weak symbols, which we all set to null (indicating that the
@@ -685,7 +685,7 @@ impl<'mir, 'tcx> MiriMachine<'mir, 'tcx> {
                 Self::add_extern_static(
                     this,
                     "environ",
-                    this.machine.env_vars.environ.unwrap().ptr,
+                    this.machine.env_vars.environ.as_ref().unwrap().ptr,
                 );
             }
             "android" => {

src/shims/env.rs

@@ -87,8 +87,8 @@ impl<'tcx> EnvVars<'tcx> {
             ecx.deallocate_ptr(ptr, None, MiriMemoryKind::Runtime.into())?;
         }
         // Deallocate environ var list.
-        let environ = ecx.machine.env_vars.environ.unwrap();
-        let old_vars_ptr = ecx.read_pointer(&environ)?;
+        let environ = ecx.machine.env_vars.environ.as_ref().unwrap();
+        let old_vars_ptr = ecx.read_pointer(environ)?;
         ecx.deallocate_ptr(old_vars_ptr, None, MiriMemoryKind::Runtime.into())?;
         Ok(())
     }
@@ -431,8 +431,8 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     fn update_environ(&mut self) -> InterpResult<'tcx> {
         let this = self.eval_context_mut();
         // Deallocate the old environ list, if any.
-        if let Some(environ) = this.machine.env_vars.environ {
-            let old_vars_ptr = this.read_pointer(&environ)?;
+        if let Some(environ) = this.machine.env_vars.environ.as_ref() {
+            let old_vars_ptr = this.read_pointer(environ)?;
             this.deallocate_ptr(old_vars_ptr, None, MiriMemoryKind::Runtime.into())?;
         } else {
             // No `environ` allocated yet, let's do that.
@@ -459,7 +459,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
             let place = this.project_field(&vars_place, idx)?;
             this.write_pointer(var, &place)?;
         }
-        this.write_pointer(vars_place.ptr, &this.machine.env_vars.environ.unwrap())?;
+        this.write_pointer(vars_place.ptr, &this.machine.env_vars.environ.clone().unwrap())?;
 
         Ok(())
     }

src/shims/unix/macos/foreign_items.rs

@@ -86,7 +86,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
             "_NSGetEnviron" => {
                 let [] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
                 this.write_pointer(
-                    this.machine.env_vars.environ.expect("machine must be initialized").ptr,
+                    this.machine.env_vars.environ.as_ref().expect("machine must be initialized").ptr,
                     dest,
                 )?;
             }