Fix a build warning. (swiftlang#13985)

Greg Parker · web-flow · commit 495326228890 · 2018-01-17T14:56:22.000-08:00
"specified comparator type does not provide a const call operator"
diff --git a/lib/PrintAsObjC/PrintAsObjC.cpp b/lib/PrintAsObjC/PrintAsObjC.cpp
@@ -2062,7 +2062,7 @@ using SmallSetVector =
 template <typename T>
 struct PointerLikeComparator {
   using Traits = llvm::PointerLikeTypeTraits<T>;
-  bool operator()(T lhs, T rhs) {
+  bool operator()(T lhs, T rhs) const {
     return std::less<void*>()(Traits::getAsVoidPointer(lhs),
                               Traits::getAsVoidPointer(rhs));
   }

Original file line number	Diff line number	Diff line change
`@@ -2062,7 +2062,7 @@ using SmallSetVector =`
`2062`	`2062`	`template <typename T>`
`2063`	`2063`	`struct PointerLikeComparator {`
`2064`	`2064`	`using Traits = llvm::PointerLikeTypeTraits<T>;`
`2065`		`- bool operator()(T lhs, T rhs) {`
	`2065`	`+ bool operator()(T lhs, T rhs) const {`
`2066`	`2066`	`return std::less<void*>()(Traits::getAsVoidPointer(lhs),`
`2067`	`2067`	`Traits::getAsVoidPointer(rhs));`
`2068`	`2068`	`}`