c++ IRGen. In trivial cases that object is going into static

storage and thus is implicitly zero-initialized, no need to
do C++11 memory model. This patch unconditionally detects
such condition and zeroinitializer's the variable.
Patch has been commented on and OKed by Doug off-line.
// rdar://12897704


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@172144 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 18 insertions, 0 deletions

diff --git a/test/CodeGenCXX/cxx11-trivial-initializer-struct.cpp b/test/CodeGenCXX/cxx11-trivial-initializer-struct.cpp
new file mode 100644
index 0000000000..f38d01a467
--- /dev/null
+++ b/test/CodeGenCXX/cxx11-trivial-initializer-struct.cpp
@@ -0,0 +1,18 @@
+// RUN: %clang_cc1 -S -emit-llvm -o %t.ll %s -triple x86_64-apple-darwin10 
+// RUN: %clang_cc1 -std=c++11 -S -emit-llvm -o %t-c++11.ll %s -triple x86_64-apple-darwin10 
+// RUN: diff %t.ll  %t-c++11.ll
+
+// rdar://12897704
+
+struct sAFSearchPos {
+    unsigned char *pos;
+    unsigned char count;
+};
+
+static volatile struct sAFSearchPos testPositions;
+
+static volatile struct sAFSearchPos arrayPositions[100][10][5];
+
+int main() {
+  return testPositions.count + arrayPositions[10][4][3].count; 
+}