[Sema] Resolve placeholder types before type deduction to silence

spurious `-Warc-repeated-use-of-weak` warnings

The spurious -Warc-repeated-use-of-weak warnings are issued when an
initializer expression uses a weak ObjC pointer.

My first attempt to silence the warnings (r350917) caused clang to
reject code that is legal in C++17. The patch is based on the feedback I
received from Richard when the patch was reverted.

http://lists.llvm.org/pipermail/cfe-commits/Week-of-Mon-20190422/268945.html
http://lists.llvm.org/pipermail/cfe-commits/Week-of-Mon-20190422/268943.html

Differential Revision: https://reviews.llvm.org/D62645

llvm-svn: 365382

1 files changed, 14 insertions, 2 deletions

diff --git a/clang/test/SemaObjC/arc-repeated-weak.mm b/clang/test/SemaObjC/arc-repeated-weak.mm
index 4eec4d2fe69..6c7a6292f99 100644
--- a/clang/test/SemaObjC/arc-repeated-weak.mm
+++ b/clang/test/SemaObjC/arc-repeated-weak.mm
@@ -1,5 +1,5 @@
-// RUN: %clang_cc1 -fsyntax-only -fobjc-runtime-has-weak -fobjc-arc -fblocks -Wno-objc-root-class -std=c++11 -Warc-repeated-use-of-weak -verify %s
-// RUN: %clang_cc1 -fsyntax-only -fobjc-runtime-has-weak -fobjc-weak -fblocks -Wno-objc-root-class -std=c++11 -Warc-repeated-use-of-weak -verify %s
+// RUN: %clang_cc1 -fsyntax-only -fobjc-runtime-has-weak -fobjc-arc -fblocks -Wno-objc-root-class -std=c++14 -Warc-repeated-use-of-weak -verify %s
+// RUN: %clang_cc1 -fsyntax-only -fobjc-runtime-has-weak -fobjc-weak -fblocks -Wno-objc-root-class -std=c++14 -Warc-repeated-use-of-weak -verify %s
 
 @interface Test {
 @public
@@ -467,6 +467,18 @@ void foo() {
   __typeof__(NSBundle2.foo2.weakProp) t5;
 }
 
+void testAuto() {
+  auto __weak wp = NSBundle2.foo2.weakProp;
+}
+
+void testLambdaCaptureInit() {
+  [capture(NSBundle2.foo2.weakProp)] {} ();
+}
+
+void testAutoNew() {
+  auto p = new auto(NSBundle2.foo2.weakProp);
+}
+
 // This used to crash in the constructor of WeakObjectProfileTy when a
 // DeclRefExpr was passed that didn't reference a VarDecl.