[Clang] implement -fno-eliminate-unused-debug-types

Fixes pr/11710.
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>

Resubmit after breaking Windows and OSX builds.

Reviewed By: dblaikie

Differential Revision: https://reviews.llvm.org/D80242

1 files changed, 13 insertions, 6 deletions

diff --git a/clang/lib/CodeGen/CGDecl.cpp b/clang/lib/CodeGen/CGDecl.cpp
index 1729c7ed..0ad5050 100644
--- a/clang/lib/CodeGen/CGDecl.cpp
+++ b/clang/lib/CodeGen/CGDecl.cpp
@@ -100,11 +100,19 @@ void CodeGenFunction::EmitDecl(const Decl &D) {
   case Decl::ObjCTypeParam:
   case Decl::Binding:
     llvm_unreachable("Declaration should not be in declstmts!");
-  case Decl::Function:  // void X();
   case Decl::Record:    // struct/union/class X;
+  case Decl::CXXRecord: // struct/union/class X; [C++]
+    if (CGDebugInfo *DI = getDebugInfo())
+      if (cast<RecordDecl>(D).getDefinition())
+        DI->EmitAndRetainType(getContext().getRecordType(cast<RecordDecl>(&D)));
+    return;
   case Decl::Enum:      // enum X;
+    if (CGDebugInfo *DI = getDebugInfo())
+      if (cast<EnumDecl>(D).getDefinition())
+        DI->EmitAndRetainType(getContext().getEnumType(cast<EnumDecl>(&D)));
+    return;
+  case Decl::Function:     // void X();
   case Decl::EnumConstant: // enum ? { X = ? }
-  case Decl::CXXRecord: // struct/union/class X; [C++]
   case Decl::StaticAssert: // static_assert(X, ""); [C++0x]
   case Decl::Label:        // __label__ x;
   case Decl::Import:
@@ -157,12 +165,11 @@ void CodeGenFunction::EmitDecl(const Decl &D) {
 
   case Decl::Typedef:      // typedef int X;
   case Decl::TypeAlias: {  // using X = int; [C++0x]
-    const TypedefNameDecl &TD = cast<TypedefNameDecl>(D);
-    QualType Ty = TD.getUnderlyingType();
-
+    QualType Ty = cast<TypedefNameDecl>(D).getUnderlyingType();
+    if (CGDebugInfo *DI = getDebugInfo())
+      DI->EmitAndRetainType(Ty);
     if (Ty->isVariablyModifiedType())
       EmitVariablyModifiedType(Ty);
-
     return;
   }
   }