[coroutines] Fix assertion during -Wuninitialized analysis

Summary: @rsmith Is there a better place to put this test?

Reviewers: GorNishanov, rsmith

Reviewed By: GorNishanov

Subscribers: cfe-commits, rsmith

Differential Revision: https://reviews.llvm.org/D33660

llvm-svn: 304331

2 files changed, 45 insertions, 1 deletions

diff --git a/clang/test/SemaCXX/coreturn.cpp b/clang/test/SemaCXX/coreturn.cpp
index 0ec94d1b599..7265d7c19c2 100644
--- a/clang/test/SemaCXX/coreturn.cpp
+++ b/clang/test/SemaCXX/coreturn.cpp
@@ -1,4 +1,4 @@
-// RUN: %clang_cc1 -triple x86_64-apple-darwin9 %s -std=c++14 -fcoroutines-ts -fsyntax-only -Wignored-qualifiers -Wno-error=return-type -verify -fblocks -Wno-unreachable-code -Wno-unused-value
+// RUN: %clang_cc1 -triple x86_64-apple-darwin9 %s -std=c++14 -fcoroutines-ts -fsyntax-only -Wignored-qualifiers -Wno-error=return-type -verify -fblocks -Wall -Wextra -Wno-error=unreachable-code
 #include "Inputs/std-coroutine.h"
 
 using std::experimental::suspend_always;
diff --git a/clang/test/SemaCXX/coroutine-uninitialized-warning-crash.cpp b/clang/test/SemaCXX/coroutine-uninitialized-warning-crash.cpp
new file mode 100644
index 00000000000..5bdb232d530
--- /dev/null
+++ b/clang/test/SemaCXX/coroutine-uninitialized-warning-crash.cpp
@@ -0,0 +1,44 @@
+// RUN: %clang_cc1 -triple x86_64-apple-darwin9 %s -std=c++14 -fcoroutines-ts -fsyntax-only -Wall -Wextra -Wuninitialized  -fblocks
+#include "Inputs/std-coroutine.h"
+
+using namespace std::experimental;
+
+
+struct A {
+  bool await_ready() { return true; }
+  int await_resume() { return 42; }
+  template <typename F>
+  void await_suspend(F) {}
+};
+
+
+struct coro_t {
+  struct promise_type {
+    coro_t get_return_object() { return {}; }
+    suspend_never initial_suspend() { return {}; }
+    suspend_never final_suspend() { return {}; }
+    A yield_value(int) { return {}; }
+    void return_void() {}
+    static void unhandled_exception() {}
+  };
+};
+
+coro_t f(int n) {
+  if (n == 0)
+    co_return;
+  co_yield 42;
+  int x = co_await A{};
+}
+
+template <class Await>
+coro_t g(int n) {
+  if (n == 0)
+    co_return;
+  co_yield 42;
+  int x = co_await Await{};
+}
+
+int main() {
+  f(0);
+  g<A>(0);
+}