From 8fd292ed9018202a8ec132c8d691bb34dbb816fe Mon Sep 17 00:00:00 2001
From: Warren Ristow <warren.ristow@sony.com>
Date: Thu, 2 Feb 2017 17:53:34 +0000
Subject: [PATCH] Prevent ICE in dllexport class with _Atomic data member
Guard against a null pointer dereference that caused Clang to crash
when processing a class containing an _Atomic qualified data member,
and that is tagged with 'dllexport'.
Differential Revision: https://reviews.llvm.org/D29208
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@293911 91177308-0d34-0410-b5e6-96231b3b80d8
---
lib/CodeGen/CGClass.cpp | 9 +++++----
test/CodeGenCXX/atomic-dllexport.cpp | 9 +++++++++
2 files changed, 14 insertions(+), 4 deletions(-)
create mode 100644 test/CodeGenCXX/atomic-dllexport.cpp
diff --git a/lib/CodeGen/CGClass.cpp b/lib/CodeGen/CGClass.cpp
index c3e907e9cd5..03c3358bd8b 100644
--- a/lib/CodeGen/CGClass.cpp
+++ b/lib/CodeGen/CGClass.cpp
@@ -1131,10 +1131,11 @@ namespace {
RHS = EC->getSubExpr();
if (!RHS)
return nullptr;
- MemberExpr *ME2 = dyn_cast<MemberExpr>(RHS);
- if (dyn_cast<FieldDecl>(ME2->getMemberDecl()) != Field)
- return nullptr;
- return Field;
+ if (MemberExpr *ME2 = dyn_cast<MemberExpr>(RHS)) {
+ if (ME2->getMemberDecl() == Field)
+ return Field;
+ }
+ return nullptr;
} else if (CXXMemberCallExpr *MCE = dyn_cast<CXXMemberCallExpr>(S)) {
CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(MCE->getCalleeDecl());
if (!(MD && isMemcpyEquivalentSpecialMember(MD)))
diff --git a/test/CodeGenCXX/atomic-dllexport.cpp b/test/CodeGenCXX/atomic-dllexport.cpp
new file mode 100644
index 00000000000..ae142224316
--- /dev/null
+++ b/test/CodeGenCXX/atomic-dllexport.cpp
@@ -0,0 +1,9 @@
+// RUN: %clang_cc1 -triple i686-windows-msvc -emit-llvm -std=c++11 -fms-extensions -O0 -o - %s | FileCheck --check-prefix=M32 %s
+// RUN: %clang_cc1 -triple x86_64-windows-msvc -emit-llvm -std=c++11 -fms-extensions -O0 -o - %s | FileCheck --check-prefix=M64 %s
+
+struct __declspec(dllexport) SomeStruct {
+ // Copy assignment operator should be produced, and exported:
+ // M32: define weak_odr dllexport x86_thiscallcc dereferenceable({{[0-9]+}}) %struct.SomeStruct* @"\01??4SomeStruct@@QAEAAU0@ABU0@@Z"
+ // M64: define weak_odr dllexport dereferenceable({{[0-9]+}}) %struct.SomeStruct* @"\01??4SomeStruct@@QEAAAEAU0@AEBU0@@Z"
+ _Atomic(int) mData;
+};
--
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