[CS] Ensure we trap in getOverloadChoice if the overload is missing

hamishknight · hamishknight · commit 6fb6bc3628ec · 2025-09-14T11:59:20.000+01:00
Using `*` previously meant we'd invoke undefined behavior.
diff --git a/include/swift/Sema/ConstraintSystem.h b/include/swift/Sema/ConstraintSystem.h
@@ -1764,7 +1764,7 @@ class Solution {
   /// Retrieve the overload choice associated with the given
   /// locator.
   SelectedOverload getOverloadChoice(ConstraintLocator *locator) const {
-    return *getOverloadChoiceIfAvailable(locator);
+    return getOverloadChoiceIfAvailable(locator).value();
   }
 
   /// Retrieve the overload choice for the callee associated with the given

Original file line number	Diff line number	Diff line change
`@@ -1764,7 +1764,7 @@ class Solution {`
`1764`	`1764`	`/// Retrieve the overload choice associated with the given`
`1765`	`1765`	`/// locator.`
`1766`	`1766`	`SelectedOverload getOverloadChoice(ConstraintLocator *locator) const {`
`1767`		`- return *getOverloadChoiceIfAvailable(locator);`
	`1767`	`+ return getOverloadChoiceIfAvailable(locator).value();`
`1768`	`1768`	`}`
`1769`	`1769`
`1770`	`1770`	`/// Retrieve the overload choice for the callee associated with the given`