mir: Gather move at SwitchInt, Assert terminators

fpoli · fpoli · commit fe0260fbf892 · 2018-02-15T15:18:14.000+01:00
Previously, "_1" was not marked as "definitely uninitialized" after a "switchInt(move _1)" terminator. Related discussion: https://internals.rust-lang.org/t/why-is-2-definitely-initialized-after-switchint-move-2/6760
diff --git a/src/librustc_mir/dataflow/move_paths/builder.rs b/src/librustc_mir/dataflow/move_paths/builder.rs
@@ -353,9 +353,12 @@ impl<'b, 'a, 'gcx, 'tcx> Gatherer<'b, 'a, 'gcx, 'tcx> {
                 self.gather_move(&Place::Local(RETURN_PLACE));
             }
 
-            TerminatorKind::Assert { .. } |
-            TerminatorKind::SwitchInt { .. } => {
-                // branching terminators - these don't move anything
+            TerminatorKind::Assert { ref cond, .. } => {
+                self.gather_operand(cond);
+            }
+
+            TerminatorKind::SwitchInt { ref discr, .. } => {
+                self.gather_operand(discr);
             }
 
             TerminatorKind::Yield { ref value, .. } => {

Original file line number	Diff line number	Diff line change
`@@ -353,9 +353,12 @@ impl<'b, 'a, 'gcx, 'tcx> Gatherer<'b, 'a, 'gcx, 'tcx> {`
`353`	`353`	`self.gather_move(&Place::Local(RETURN_PLACE));`
`354`	`354`	`}`
`355`	`355`
`356`		`- TerminatorKind::Assert { .. } \|`
`357`		`- TerminatorKind::SwitchInt { .. } => {`
`358`		`- // branching terminators - these don't move anything`
	`356`	`+ TerminatorKind::Assert { ref cond, .. } => {`
	`357`	`+ self.gather_operand(cond);`
	`358`	`+ }`
	`359`	`+`
	`360`	`+ TerminatorKind::SwitchInt { ref discr, .. } => {`
	`361`	`+ self.gather_operand(discr);`
`359`	`362`	`}`
`360`	`363`
`361`	`364`	`TerminatorKind::Yield { ref value, .. } => {`