From a932cb6d093902fe7ecd36f4bd5fb54fa1400607 Mon Sep 17 00:00:00 2001
From: Paul Robinson <paul_robinson@playstation.sony.com>
Date: Tue, 10 Feb 2015 15:30:02 +0000
Subject: [PATCH] Explicitly initialize a flag in a default constructor. Works
 around a Visual C++ issue.

Patch by Douglas Yung!



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228699 91177308-0d34-0410-b5e6-96231b3b80d8
---
 .../CodeGen/TargetLoweringObjectFileImpl.h    |  2 +
 test/CodeGen/X86/init-priority.ll             | 51 +++++++++++++++++++
 2 files changed, 53 insertions(+)
 create mode 100644 test/CodeGen/X86/init-priority.ll

diff --git a/include/llvm/CodeGen/TargetLoweringObjectFileImpl.h b/include/llvm/CodeGen/TargetLoweringObjectFileImpl.h
index 9209e1c67c1..abf6a2a2467 100644
--- a/include/llvm/CodeGen/TargetLoweringObjectFileImpl.h
+++ b/include/llvm/CodeGen/TargetLoweringObjectFileImpl.h
@@ -36,6 +36,8 @@ class TargetLoweringObjectFileELF : public TargetLoweringObjectFile {
   bool UseInitArray;
 
 public:
+  TargetLoweringObjectFileELF() : UseInitArray(false) {}
+
   virtual ~TargetLoweringObjectFileELF() {}
 
   void emitPersonalityValue(MCStreamer &Streamer, const TargetMachine &TM,
diff --git a/test/CodeGen/X86/init-priority.ll b/test/CodeGen/X86/init-priority.ll
new file mode 100644
index 00000000000..a0cff237f18
--- /dev/null
+++ b/test/CodeGen/X86/init-priority.ll
@@ -0,0 +1,51 @@
+; RUN: llc < %s -mtriple=x86_64-unknown-freebsd9 | FileCheck %s
+
+; Check that our compiler never emits global constructors
+; inside the .init_array section when building for a non-Linux ELF target.
+; Because of this, the test depends on UseInitArray behavior under FreeBSD
+; as found in Generic_ELF::addClangTargetOptions().
+
+; This is to workaround a Visual Studio bug which causes field
+; UseInitArray to be left uninitialized instead of being 
+; zero-initialized (as specified in [dcl.init]p7).
+; This workaround consists in providing a user default constructor
+; that explicitly initializes field UseInitArray.
+
+%class.C = type { i8 }
+%class.D = type { i8 }
+
+@c1 = global %class.C zeroinitializer, align 1
+@d1 = global %class.D zeroinitializer, align 1
+@llvm.global_ctors = appending global [2 x { i32, void ()* }] [{ i32, void ()* } { i32 101, void ()* @_GLOBAL__I_000101 }, { i32, void ()* } { i32 65535, void ()* @_GLOBAL__I_a }]
+
+define linkonce_odr void @_ZN1CC1Ev(%class.C* nocapture %this) {
+entry:
+  ret void
+}
+
+define linkonce_odr void @_ZN1DC1Ev(%class.D* nocapture %this) {
+entry:
+  ret void
+}
+
+define linkonce_odr void @_ZN1DC2Ev(%class.D* nocapture %this) {
+entry:
+  ret void
+}
+
+define linkonce_odr void @_ZN1CC2Ev(%class.C* nocapture %this) {
+entry:
+  ret void
+}
+
+define internal void @_GLOBAL__I_000101() nounwind readnone {
+entry:
+  ret void
+}
+
+define internal void @_GLOBAL__I_a() nounwind readnone {
+entry:
+  ret void
+}
+
+; CHECK-NOT: .init_array