From 2f2c90e733a703f69cf13ae79ec623901d42ba2c Mon Sep 17 00:00:00 2001
From: Oliver Schneider <git-spam-no-reply9815368754983@oli-obk.de>
Date: Thu, 25 Jan 2018 14:15:56 +0100
Subject: [PATCH] Destructure Rc wrapped ErrorKind in miri

---
 src/librustc_mir/interpret/const_eval.rs   | 14 ++++++++------
 src/librustc_mir/interpret/eval_context.rs | 11 ++++++-----
 src/librustc_mir/transform/instcombine.rs  |  6 +-----
 3 files changed, 15 insertions(+), 16 deletions(-)

diff --git a/src/librustc_mir/interpret/const_eval.rs b/src/librustc_mir/interpret/const_eval.rs
index c2bb9f2efe1..611633163fa 100644
--- a/src/librustc_mir/interpret/const_eval.rs
+++ b/src/librustc_mir/interpret/const_eval.rs
@@ -235,13 +235,15 @@ impl<'mir, 'tcx> super::Machine<'mir, 'tcx> for CompileTimeEvaluator {
         }
         let mir = match ecx.load_mir(instance.def) {
             Ok(mir) => mir,
-            Err(EvalError { kind: EvalErrorKind::NoMirFor(path), .. }) => {
-                return Err(
-                    ConstEvalError::NeedsRfc(format!("calling extern function `{}`", path))
-                        .into(),
-                );
+            Err(err) => {
+                if let EvalErrorKind::NoMirFor(ref path) = *err.kind {
+                    return Err(
+                        ConstEvalError::NeedsRfc(format!("calling extern function `{}`", path))
+                            .into(),
+                    );
+                }
+                return Err(err);
             }
-            Err(other) => return Err(other),
         };
         let (return_place, return_to_block) = match destination {
             Some((place, block)) => (place, StackPopCleanup::Goto(block)),
diff --git a/src/librustc_mir/interpret/eval_context.rs b/src/librustc_mir/interpret/eval_context.rs
index e759407f431..eaa1bcb96a9 100644
--- a/src/librustc_mir/interpret/eval_context.rs
+++ b/src/librustc_mir/interpret/eval_context.rs
@@ -1513,11 +1513,12 @@ impl<'a, 'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> EvalContext<'a, 'mir, 'tcx, M
                 write!(msg, ":").unwrap();
 
                 match self.stack[frame].get_local(local) {
-                    Err(EvalError { kind: EvalErrorKind::DeadLocal, .. }) => {
-                        write!(msg, " is dead").unwrap();
-                    }
                     Err(err) => {
-                        panic!("Failed to access local: {:?}", err);
+                        if let EvalErrorKind::DeadLocal = *err.kind {
+                            write!(msg, " is dead").unwrap();
+                        } else {
+                            panic!("Failed to access local: {:?}", err);
+                        }
                     }
                     Ok(Value::ByRef(ptr, align)) => {
                         match ptr.into_inner_primval() {
@@ -1576,7 +1577,7 @@ impl<'a, 'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> EvalContext<'a, 'mir, 'tcx, M
     }
 
     pub fn report(&self, e: &mut EvalError, as_err: bool, explicit_span: Option<Span>) {
-        if let EvalErrorKind::TypeckError = e.kind {
+        if let EvalErrorKind::TypeckError = *e.kind {
             return;
         }
         if let Some(ref mut backtrace) = e.backtrace {
diff --git a/src/librustc_mir/transform/instcombine.rs b/src/librustc_mir/transform/instcombine.rs
index 25787608e39..640fd7cadab 100644
--- a/src/librustc_mir/transform/instcombine.rs
+++ b/src/librustc_mir/transform/instcombine.rs
@@ -362,12 +362,8 @@ impl<'b, 'a, 'tcx:'b> OptimizationFinder<'b, 'a, 'tcx> {
                             )
                         } else {
                             if overflow {
-                                use rustc::mir::interpret::EvalError;
                                 use rustc::mir::interpret::EvalErrorKind;
-                                let mut err = EvalError {
-                                    kind: EvalErrorKind::OverflowingMath,
-                                    backtrace: None,
-                                };
+                                let mut err = EvalErrorKind::OverflowingMath.into();
                                 ecx.report(&mut err, false, Some(span));
                                 return None;
                             }