Correctly handle conditional operators involving throw.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@90800 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 15 insertions, 4 deletions

diff --git a/lib/CodeGen/CGExprScalar.cpp b/lib/CodeGen/CGExprScalar.cpp
index c1cbecc9fa..0ad139af4c 100644
--- a/lib/CodeGen/CGExprScalar.cpp
+++ b/lib/CodeGen/CGExprScalar.cpp
@@ -1868,10 +1868,11 @@ VisitConditionalOperator(const ConditionalOperator *E) {
 
   CGF.EmitBlock(ContBlock);
 
-  if (!LHS || !RHS) {
-    assert(E->getType()->isVoidType() && "Non-void value should have a value");
-    return 0;
-  }
+  // If the LHS or RHS is a throw expression, it will be legitimately null.
+  if (!LHS)
+    return RHS;
+  if (!RHS)
+    return LHS;
 
   // Create a PHI node for the real part.
   llvm::PHINode *PN = Builder.CreatePHI(LHS->getType(), "cond");
diff --git a/test/CodeGenCXX/throw-expressions.cpp b/test/CodeGenCXX/throw-expressions.cpp
new file mode 100644
index 0000000000..7fe556312b
--- /dev/null
+++ b/test/CodeGenCXX/throw-expressions.cpp
@@ -0,0 +1,10 @@
+// RUN: clang-cc -emit-llvm-only -verify %s
+
+int val = 42;
+int& test1() {
+  return throw val, val;
+}
+
+int test2() {
+  return val ? throw val : val;
+}