commit a8cfb77adf591f0e811645876bd3ae89a6596dcd
author Doug Gregor <dgregor@apple.com> Tue Oct 31 06:48:58 2017 -0700
committer GitHub <noreply@github.com> Tue Oct 31 06:48:58 2017 -0700
tree 82b462dcd85be94803b2d092efd1efaef4859329
parent 3821f6e5c84e389197f903b35fd35ce812ac4801
parent f896b915901da9cce8af88512cad848940f605ab

Merge pull request #12680 from DougGregor/importer-bridged-typedef-4.1

[Clang importer] Fix bridging of the underlying types of typedefs.

lib/SILOptimizer/IPO/DeadFunctionElimination.cpp

diff --git a/lib/SILOptimizer/IPO/DeadFunctionElimination.cpp b/lib/SILOptimizer/IPO/DeadFunctionElimination.cpp
index 8162028..18fee20 100644
--- a/lib/SILOptimizer/IPO/DeadFunctionElimination.cpp
+++ b/lib/SILOptimizer/IPO/DeadFunctionElimination.cpp
@@ -223,15 +223,22 @@
         auto id = component.getComputedPropertyId();
         switch (id.getKind()) {
         case KeyPathPatternComponent::ComputedPropertyId::DeclRef: {
-          auto decl = cast<AbstractFunctionDecl>(id.getDeclRef().getDecl());
-          if (auto clas = dyn_cast<ClassDecl>(decl->getDeclContext())) {
-            ensureAliveClassMethod(getMethodInfo(decl, /*witness*/ false),
-                                   dyn_cast<FuncDecl>(decl),
-                                   clas);
-          } else if (isa<ProtocolDecl>(decl->getDeclContext())) {
-            ensureAliveProtocolMethod(getMethodInfo(decl, /*witness*/ true));
+          auto declRef = id.getDeclRef();
+          if (declRef.isForeign) {
+            // Nothing to do here: foreign functions aren't ours to be deleting.
+            // (And even if they were, they're ObjC-dispatched and thus anchored
+            // already: see isAnchorFunction)
           } else {
-            llvm_unreachable("key path keyed by a non-class, non-protocol method");
+            auto decl = cast<AbstractFunctionDecl>(declRef.getDecl());
+            if (auto clas = dyn_cast<ClassDecl>(decl->getDeclContext())) {
+              ensureAliveClassMethod(getMethodInfo(decl, /*witness*/ false),
+                                     dyn_cast<FuncDecl>(decl),
+                                     clas);
+            } else if (isa<ProtocolDecl>(decl->getDeclContext())) {
+              ensureAliveProtocolMethod(getMethodInfo(decl, /*witness*/ true));
+            } else {
+              llvm_unreachable("key path keyed by a non-class, non-protocol method");
+            }
           }
           break;
         }

test/SILOptimizer/Inputs/keypaths_objc.h

diff --git a/test/SILOptimizer/Inputs/keypaths_objc.h b/test/SILOptimizer/Inputs/keypaths_objc.h
new file mode 100644
index 0000000..f1a379b
--- /dev/null
+++ b/test/SILOptimizer/Inputs/keypaths_objc.h
@@ -0,0 +1,14 @@
+@import Foundation;
+
+@interface ObjCFoo
+
+@property(readonly) NSString *_Nonnull objcProp;
+
+@end
+
+
+@interface ObjCFoo (Extras)
+
+@property(readonly) NSString *_Nonnull objcExtraProp;
+
+@end

test/SILOptimizer/dead_func_objc_extension_keypath.swift

diff --git a/test/SILOptimizer/dead_func_objc_extension_keypath.swift b/test/SILOptimizer/dead_func_objc_extension_keypath.swift
new file mode 100644
index 0000000..ca04f4c
--- /dev/null
+++ b/test/SILOptimizer/dead_func_objc_extension_keypath.swift
@@ -0,0 +1,7 @@
+// RUN: %target-swift-frontend %s -O -emit-sil -import-objc-header %S/Inputs/keypaths_objc.h
+// REQUIRES: objc_interop
+
+import Foundation
+public func test_nocrash_rdar34913689() {
+  _ = \ObjCFoo.objcExtraProp
+}