Debug Info: Support for DW_AT_export_symbols for anonymous structs

This implements the DWARF 5 feature described in:

http://dwarfstd.org/ShowIssue.php?issue=141212.1

To support recognizing anonymous structs:

  struct A {
    struct { // Anonymous struct
        int y;
    };
  } a;

This patch adds support in CGDebugInfo::CreateLimitedType(...) for this new flag and an accompanying test to verify this feature.

Differential Revision: https://reviews.llvm.org/D66667

llvm-svn: 370107

1 files changed, 6 insertions, 1 deletions

diff --git a/clang/lib/CodeGen/CGDebugInfo.cpp b/clang/lib/CodeGen/CGDebugInfo.cpp
index 422fbc1e290..b1f82d47d44 100644
--- a/clang/lib/CodeGen/CGDebugInfo.cpp
+++ b/clang/lib/CodeGen/CGDebugInfo.cpp
@@ -3121,7 +3121,8 @@ llvm::DICompositeType *CGDebugInfo::CreateLimitedType(const RecordType *Ty) {
 
   SmallString<256> Identifier = getTypeIdentifier(Ty, CGM, TheCU);
 
-  // Explicitly record the calling convention for C++ records.
+  // Explicitly record the calling convention and export symbols for C++
+  // records.
   auto Flags = llvm::DINode::FlagZero;
   if (auto CXXRD = dyn_cast<CXXRecordDecl>(RD)) {
     if (CGM.getCXXABI().getRecordArgABI(CXXRD) == CGCXXABI::RAA_Indirect)
@@ -3132,6 +3133,10 @@ llvm::DICompositeType *CGDebugInfo::CreateLimitedType(const RecordType *Ty) {
     // Record if a C++ record is non-trivial type.
     if (!CXXRD->isTrivial())
       Flags |= llvm::DINode::FlagNonTrivial;
+
+    // Record exports it symbols to the containing structure.
+    if (CXXRD->isAnonymousStructOrUnion())
+        Flags |= llvm::DINode::FlagExportSymbols;
   }
 
   llvm::DICompositeType *RealDecl = DBuilder.createReplaceableCompositeType(