Don't copy or initialize empty classes. Fixes PR7012.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@102891 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/CGExprAgg.cpp b/lib/CodeGen/CGExprAgg.cpp
index 84841bf..96274cb 100644
--- a/lib/CodeGen/CGExprAgg.cpp
+++ b/lib/CodeGen/CGExprAgg.cpp
@@ -738,6 +738,14 @@
bool isVolatile) {
assert(!Ty->isAnyComplexType() && "Shouldn't happen for complex");
+ // Ignore empty classes in C++.
+ if (getContext().getLangOptions().CPlusPlus) {
+ if (const RecordType *RT = Ty->getAs<RecordType>()) {
+ if (cast<CXXRecordDecl>(RT->getDecl())->isEmpty())
+ return;
+ }
+ }
+
// Aggregate assignment turns into llvm.memcpy. This is almost valid per
// C99 6.5.16.1p3, which states "If the value being stored in an object is
// read from another object that overlaps in anyway the storage of the first
diff --git a/lib/CodeGen/CodeGenFunction.cpp b/lib/CodeGen/CodeGenFunction.cpp
index 34b9049..d3bf164 100644
--- a/lib/CodeGen/CodeGenFunction.cpp
+++ b/lib/CodeGen/CodeGenFunction.cpp
@@ -473,6 +473,14 @@
}
void CodeGenFunction::EmitMemSetToZero(llvm::Value *DestPtr, QualType Ty) {
+ // Ignore empty classes in C++.
+ if (getContext().getLangOptions().CPlusPlus) {
+ if (const RecordType *RT = Ty->getAs<RecordType>()) {
+ if (cast<CXXRecordDecl>(RT->getDecl())->isEmpty())
+ return;
+ }
+ }
+
const llvm::Type *BP = llvm::Type::getInt8PtrTy(VMContext);
if (DestPtr->getType() != BP)
DestPtr = Builder.CreateBitCast(DestPtr, BP, "tmp");
diff --git a/test/CodeGenCXX/new.cpp b/test/CodeGenCXX/new.cpp
index ca7c52f..cc62885 100644
--- a/test/CodeGenCXX/new.cpp
+++ b/test/CodeGenCXX/new.cpp
@@ -90,7 +90,7 @@
return new(1, 2, 3.45, 100) A;
}
-struct B { };
+struct B { int a; };
void t11() {
// CHECK: call noalias i8* @_Znwm
// CHECK: call void @llvm.memset.p0i8.i64(