From ce4fdefbd824271c342ab253b5e475ab9dc91be9 Mon Sep 17 00:00:00 2001
From: Ariel Ben-Yehuda <arielb1@mail.tau.ac.il>
Date: Thu, 9 Jun 2016 17:23:23 +0300
Subject: [PATCH] fix issues

---
 src/librustc_driver/driver.rs         | 3 ++-
 src/librustc_mir/build/cfg.rs         | 5 ++++-
 src/librustc_mir/build/matches/mod.rs | 3 +++
 src/rustc/Cargo.lock                  | 1 +
 4 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/src/librustc_driver/driver.rs b/src/librustc_driver/driver.rs
index ce132a0487079..1205d688b85a8 100644
--- a/src/librustc_driver/driver.rs
+++ b/src/librustc_driver/driver.rs
@@ -980,7 +980,8 @@ pub fn phase_3_run_analysis_passes<'tcx, F, R>(sess: &'tcx Session,
             passes.push_pass(box mir::transform::simplify_cfg::SimplifyCfg::new("initial"));
             passes.push_pass(box mir::transform::qualify_consts::QualifyAndPromoteConstants);
             passes.push_pass(box mir::transform::type_check::TypeckMir);
-            passes.push_pass(box mir::transform::simplify_branches::SimplifyBranches::new("initial"));
+            passes.push_pass(
+                box mir::transform::simplify_branches::SimplifyBranches::new("initial"));
             passes.push_pass(box mir::transform::simplify_cfg::SimplifyCfg::new("qualify-consts"));
             // And run everything.
             passes.run_passes(tcx, &mut mir_map);
diff --git a/src/librustc_mir/build/cfg.rs b/src/librustc_mir/build/cfg.rs
index 3bd6a7e1dd118..83f8c3b42c850 100644
--- a/src/librustc_mir/build/cfg.rs
+++ b/src/librustc_mir/build/cfg.rs
@@ -78,8 +78,11 @@ impl<'tcx> CFG<'tcx> {
                      block: BasicBlock,
                      source_info: SourceInfo,
                      kind: TerminatorKind<'tcx>) {
+        debug!("terminating block {:?} <- {:?}", block, kind);
         debug_assert!(self.block_data(block).terminator.is_none(),
-                      "terminate: block {:?} already has a terminator set", block);
+                      "terminate: block {:?}={:?} already has a terminator set",
+                      block,
+                      self.block_data(block));
         self.block_data_mut(block).terminator = Some(Terminator {
             source_info: source_info,
             kind: kind,
diff --git a/src/librustc_mir/build/matches/mod.rs b/src/librustc_mir/build/matches/mod.rs
index c57913c8e6068..b3315ab7d290f 100644
--- a/src/librustc_mir/build/matches/mod.rs
+++ b/src/librustc_mir/build/matches/mod.rs
@@ -87,6 +87,9 @@ impl<'a, 'gcx, 'tcx> Builder<'a, 'gcx, 'tcx> {
             // can't be reached - terminate them with an `unreachable`.
             let source_info = self.source_info(span);
 
+            let mut otherwise = otherwise;
+            otherwise.sort();
+            otherwise.dedup(); // variant switches can introduce duplicate target blocks
             for block in otherwise {
                 self.cfg.terminate(block, source_info, TerminatorKind::Unreachable);
             }
diff --git a/src/rustc/Cargo.lock b/src/rustc/Cargo.lock
index 50d9f61e2c160..3e8277e28ba73 100644
--- a/src/rustc/Cargo.lock
+++ b/src/rustc/Cargo.lock
@@ -87,6 +87,7 @@ dependencies = [
  "graphviz 0.0.0",
  "log 0.0.0",
  "rustc 0.0.0",
+ "rustc_data_structures 0.0.0",
  "rustc_mir 0.0.0",
  "syntax 0.0.0",
 ]