Vendor import of clang RELEASE_350/final tag r216957 (effectively, 3.5.0 release):

https://llvm.org/svn/llvm-project/cfe/tags/RELEASE_350/final@216957

1 files changed, 27 insertions, 0 deletions

diff --git a/test/CodeGenCXX/arm64-empty-struct.cpp b/test/CodeGenCXX/arm64-empty-struct.cpp
new file mode 100644
index 0000000..6fa4e95
--- /dev/null
+++ b/test/CodeGenCXX/arm64-empty-struct.cpp
@@ -0,0 +1,27 @@
+// RUN: %clang_cc1 -triple arm64-apple-ios -target-abi darwinpcs -emit-llvm -o - %s | FileCheck %s
+struct Empty {};
+
+Empty emptyvar;
+
+int take_args(int a, ...) {
+  __builtin_va_list l;
+  __builtin_va_start(l, a);
+// CHECK: call void @llvm.va_start
+
+  emptyvar = __builtin_va_arg(l, Empty);
+// CHECK: load i8**
+// CHECK-NOT: getelementptr
+// CHECK: [[EMPTY_PTR:%[a-zA-Z0-9._]+]] = bitcast i8* {{%[a-zA-Z0-9._]+}} to %struct.Empty*
+
+  // It's conceivable that EMPTY_PTR may not actually be a valid pointer
+  // (e.g. it's at the very bottom of the stack and the next page is
+  // invalid). This doesn't matter provided it's never loaded (there's no
+  // well-defined way to tell), but it becomes a problem if we do try to use it.
+// CHECK-NOT: load %struct.Empty* [[EMPTY_PTR]]
+
+  int i = __builtin_va_arg(l, int);
+// CHECK: va_arg i8** {{%[a-zA-Z0-9._]+}}, i32
+
+  __builtin_va_end(l);
+  return i;
+}