For gcc compatibility, size of a class which is zero
but has non-empty data fields, such as array of zero length,
remains zero.
// rdar://8945175
llvm-svn: 124741
diff --git a/clang/lib/AST/RecordLayoutBuilder.cpp b/clang/lib/AST/RecordLayoutBuilder.cpp
index 730ec21..a871c3d 100644
--- a/clang/lib/AST/RecordLayoutBuilder.cpp
+++ b/clang/lib/AST/RecordLayoutBuilder.cpp
@@ -1469,8 +1469,17 @@
void RecordLayoutBuilder::FinishLayout(const NamedDecl *D) {
// In C++, records cannot be of size 0.
- if (Context.getLangOptions().CPlusPlus && Size == 0)
- Size = 8;
+ if (Context.getLangOptions().CPlusPlus && Size == 0) {
+ if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(D)) {
+ // Compatibility with gcc requires a class (pod or non-pod)
+ // which is not empty but of size 0; such as having fields of
+ // array of zero-length, remains of Size 0
+ if (RD->isEmpty())
+ Size = 8;
+ }
+ else
+ Size = 8;
+ }
// Finally, round the size of the record up to the alignment of the
// record itself.
uint64_t UnpaddedSize = Size - UnfilledBitsInLastByte;