[libclang] CoroutineBody/Coreturn statements are UnexposedStmts and not Exprs

This change ensures that the libclang CXCursor represents the CoroutineBody
and the Coreturn statement using the appropriate CXCursor_UnexposedStmt kind
instead of CXCursor_UnexposedExpr. The problem with CXCursor_UnexposedExpr is
that the consumer functions assumed that CoroutineBody/Coreturn statements
were valid expressions and performed an invalid downcast to Expr causing
assertion failures or other crashes.

rdar://40204290

llvm-svn: 350282

2 files changed, 30 insertions, 3 deletions

diff --git a/clang/test/Index/coroutines.cpp b/clang/test/Index/coroutines.cpp
new file mode 100644
index 00000000000..be9ddc0b6f0
--- /dev/null
+++ b/clang/test/Index/coroutines.cpp
@@ -0,0 +1,24 @@
+// RUN: c-index-test -test-load-source all -c %s -fsyntax-only -target x86_64-apple-darwin9 -fcoroutines-ts -std=c++1z -I%S/../SemaCXX/Inputs | FileCheck %s
+#include "std-coroutine.h"
+
+using std::experimental::suspend_always;
+using std::experimental::suspend_never;
+
+struct promise_void {
+  void get_return_object();
+  suspend_always initial_suspend();
+  suspend_always final_suspend();
+  void return_void();
+  void unhandled_exception();
+};
+
+template <>
+struct std::experimental::coroutine_traits<void> { using promise_type = promise_void; };
+
+void CoroutineTestRet() {
+  co_return;
+}
+// CHECK: [[@LINE-3]]:25: UnexposedStmt=
+// CHECK-SAME: [[@LINE-4]]:25 - [[@LINE-2]]:2]
+// CHECK: [[@LINE-4]]:5: UnexposedStmt=
+// CHECK-SAME: [[@LINE-5]]:5 - [[@LINE-5]]:14]
diff --git a/clang/tools/libclang/CXCursor.cpp b/clang/tools/libclang/CXCursor.cpp
index b8c25291691..99e4319fc1f 100644
--- a/clang/tools/libclang/CXCursor.cpp
+++ b/clang/tools/libclang/CXCursor.cpp
@@ -241,16 +241,19 @@ CXCursor cxcursor::MakeCXCursor(const Stmt *S, const Decl *Parent,
   case Stmt::SEHLeaveStmtClass:
     K = CXCursor_SEHLeaveStmt;
     break;
-  
+
+  case Stmt::CoroutineBodyStmtClass:
+  case Stmt::CoreturnStmtClass:
+    K = CXCursor_UnexposedStmt;
+    break;
+
   case Stmt::ArrayTypeTraitExprClass:
   case Stmt::AsTypeExprClass:
   case Stmt::AtomicExprClass:
   case Stmt::BinaryConditionalOperatorClass:
   case Stmt::TypeTraitExprClass:
-  case Stmt::CoroutineBodyStmtClass:
   case Stmt::CoawaitExprClass:
   case Stmt::DependentCoawaitExprClass:
-  case Stmt::CoreturnStmtClass:
   case Stmt::CoyieldExprClass:
   case Stmt::CXXBindTemporaryExprClass:
   case Stmt::CXXDefaultArgExprClass: