Module Debugging: Fine-tune the condition that determines whether a type

can be found in a module.

There are externally visible anonymous types that can be found:
  typedef struct { } s; // I can be found via the typedef.
There are anonymous internal types that can be found:
  namespace { struct s {}; } // I can be found by name.

rdar://problem/24199640

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@258272 91177308-0d34-0410-b5e6-96231b3b80d8

lib/CodeGen/CGDebugInfo.cpp

@@ -1537,7 +1537,7 @@ static bool shouldOmitDefinition(CodeGenOptions::DebugInfoKind DebugKind,
                                  const LangOptions &LangOpts) {
   // Does the type exist in an imported clang module?
   if (DebugTypeExtRefs && RD->isFromASTFile() && RD->getDefinition() &&
-      RD->isExternallyVisible())
+      (RD->isExternallyVisible() || !RD->getName().empty()))
     return true;
 
   if (DebugKind > CodeGenOptions::LimitedDebugInfo)

test/Modules/ExtDebugInfo.cpp

@@ -39,8 +39,10 @@ TypedefUnion tdu;
 TypedefEnum tde;
 TypedefStruct tds;
 
+InAnonymousNamespace anon;
+
 void foo() {
-  GlobalStruct.i = GlobalUnion.i = GlobalEnum;
+  anon.i = GlobalStruct.i = GlobalUnion.i = GlobalEnum;
 }
 
 // CHECK: ![[NS:.*]] = !DINamespace(name: "DebugCXX", scope: ![[MOD:[0-9]+]],
@@ -93,4 +95,10 @@ void foo() {
 // CHECK: ![[GLOBAL_STRUCT]] = !DICompositeType(tag: DW_TAG_structure_type,
 // CHECK-SAME:                elements: !{{[0-9]+}})
 
+// CHECK: !DIGlobalVariable(name: "anon",
+// CHECK-SAME:              type: ![[GLOBAL_ANON:[0-9]+]]
+// CHECK: ![[GLOBAL_ANON]] = !DICompositeType(tag: DW_TAG_structure_type,
+// CHECK-SAME:              name: "InAnonymousNamespace", {{.*}}DIFlagFwdDecl)
+
+
 // CHECK: !DIImportedEntity(tag: DW_TAG_imported_declaration, scope: !0, entity: !"_ZTSN8DebugCXX6StructE", line: 24)

test/Modules/Inputs/DebugCXX.h

@@ -66,3 +66,9 @@ typedef struct { int i; } TypedefStruct;
 union { int i; } GlobalUnion;
 struct { int i; } GlobalStruct;
 enum { e5 = 5 } GlobalEnum;
+
+namespace {
+  namespace {
+    struct InAnonymousNamespace { int i; };
+  }
+}

test/Modules/ModuleDebugInfo.cpp

@@ -81,4 +81,8 @@
 // CHECK: !DICompositeType(tag: DW_TAG_structure_type,
 // CHECK-SAME-NOT:         name:
 
+// CHECK: !DICompositeType(tag: DW_TAG_structure_type,
+// CHECK-SAME:             name: "InAnonymousNamespace",
+// CHECK-SAME:             elements: !{{[0-9]+}})
+
 // CHECK-NEG-NOT: !DICompositeType(tag: DW_TAG_structure_type, name: "PureForwardDecl"