Sema: Fix cycle between closure type computation and EmittedMembersRequest

lib/Sema/TypeCheckDecl.cpp

@@ -25,7 +25,6 @@
 #include "TypeCheckType.h"
 #include "MiscDiagnostics.h"
 #include "swift/AST/AccessScope.h"
-#include "swift/AST/ASTMangler.h"
 #include "swift/AST/ASTPrinter.h"
 #include "swift/AST/ASTVisitor.h"
 #include "swift/AST/ASTWalker.h"
@@ -2463,21 +2462,16 @@ namespace {
 // Utility class for deterministically ordering vtable entries for
 // synthesized methods.
 struct SortedFuncList {
-  using Entry = std::pair<std::string, AbstractFunctionDecl *>;
+  using Key = std::tuple<DeclName, std::string>;
+  using Entry = std::pair<Key, AbstractFunctionDecl *>;
   SmallVector<Entry, 2> elts;
   bool sorted = false;
 
   void add(AbstractFunctionDecl *afd) {
-    Mangle::ASTMangler mangler;
-    std::string mangledName;
-    if (auto *cd = dyn_cast<ConstructorDecl>(afd))
-      mangledName = mangler.mangleConstructorEntity(cd, /*allocator=*/false);
-    else if (auto *dd = dyn_cast<DestructorDecl>(afd))
-      mangledName = mangler.mangleDestructorEntity(dd, /*deallocating=*/false);
-    else
-      mangledName = mangler.mangleEntity(afd);
+    assert(!isa<AccessorDecl>(afd));
 
-    elts.push_back(std::make_pair(mangledName, afd));
+    Key key{afd->getName(), afd->getInterfaceType().getString()};
+    elts.emplace_back(key, afd);
   }
 
   bool empty() { return elts.empty(); }

test/multifile/Inputs/rdar67842221-other.swift

@@ -0,0 +1,4 @@
+let closureValue = { () -> () in
+   class DummyClass {}
+   return ()
+}()

test/multifile/rdar67842221.swift

@@ -0,0 +1,17 @@
+// Test both orderings, and single-file vs WMO
+
+// RUN: %target-swift-frontend -emit-ir -primary-file %s %S/Inputs/rdar67842221-other.swift -module-name main
+// RUN: %target-swift-frontend -emit-ir %s -primary-file %S/Inputs/rdar67842221-other.swift -module-name main
+
+// RUN: %target-swift-frontend -emit-ir -primary-file %S/Inputs/rdar67842221-other.swift %s -module-name main
+// RUN: %target-swift-frontend -emit-ir %S/Inputs/rdar67842221-other.swift -primary-file %s -module-name main
+
+// RUN: %target-swift-frontend -emit-ir %S/Inputs/rdar67842221-other.swift %s -module-name main
+// RUN: %target-swift-frontend -emit-ir %S/Inputs/rdar67842221-other.swift %s -module-name main
+
+// The closure defines a local class; we want to make sure there is no cycle
+// between computing the semantic members of the local class (which requires
+// sorting) and computing the type of the closure value
+public func force() {
+  _ = closureValue
+}