From: Gabor Marton <martongabesz@gmail.com>
Date: Wed, 23 May 2018 14:24:02 +0000 (+0000)
Subject: [ASTImporter] Fix missing implict CXXRecordDecl in ClassTemplateSpecializationDecl
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=71643f043c06c75323a692818a440bd3fb3635e6;p=clang

[ASTImporter] Fix missing implict CXXRecordDecl in ClassTemplateSpecializationDecl

Summary:
Currently we do not import the implicit CXXRecordDecl of a
ClassTemplateSpecializationDecl. This patch fixes it.

Reviewers: a.sidorin, xazax.hun, r.stahl

Subscribers: rnkovacs, dkrupp, cfe-commits

Differential Revision: https://reviews.llvm.org/D47057

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@333086 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/AST/ASTImporter.cpp b/lib/AST/ASTImporter.cpp
index 3c69897436..7e402722b1 100644
--- a/lib/AST/ASTImporter.cpp
+++ b/lib/AST/ASTImporter.cpp
@@ -1959,14 +1959,20 @@ Decl *ASTNodeImporter::VisitRecordDecl(RecordDecl *D) {
   // but this particular declaration is not that definition, import the
   // definition and map to that.
   TagDecl *Definition = D->getDefinition();
-  if (Definition && Definition != D) {
+  if (Definition && Definition != D &&
+      // In contrast to a normal CXXRecordDecl, the implicit
+      // CXXRecordDecl of ClassTemplateSpecializationDecl is its redeclaration.
+      // The definition of the implicit CXXRecordDecl in this case is the
+      // ClassTemplateSpecializationDecl itself. Thus, we start with an extra
+      // condition in order to be able to import the implict Decl.
+      !D->isImplicit()) {
     Decl *ImportedDef = Importer.Import(Definition);
     if (!ImportedDef)
       return nullptr;
 
     return Importer.Imported(D, ImportedDef);
   }
-  
+
   // Import the major distinguishing characteristics of this record.
   DeclContext *DC, *LexicalDC;
   DeclarationName Name;
diff --git a/unittests/AST/ASTImporterTest.cpp b/unittests/AST/ASTImporterTest.cpp
index 18c8f4cc02..d5827a6a52 100644
--- a/unittests/AST/ASTImporterTest.cpp
+++ b/unittests/AST/ASTImporterTest.cpp
@@ -1360,6 +1360,22 @@ TEST_P(ASTImporterTestBase,
 }
 
 TEST_P(ASTImporterTestBase, ShouldImportImplicitCXXRecordDecl) {
+  Decl *From, *To;
+  std::tie(From, To) = getImportedDecl(
+      R"(
+      struct declToImport {
+      };
+      )",
+      Lang_CXX, "", Lang_CXX);
+
+  MatchVerifier<Decl> Verifier;
+  // Match the implicit Decl.
+  auto Matcher = cxxRecordDecl(has(cxxRecordDecl()));
+  ASSERT_TRUE(Verifier.match(From, Matcher));
+  EXPECT_TRUE(Verifier.match(To, Matcher));
+}
+
+TEST_P(ASTImporterTestBase, ShouldImportImplicitCXXRecordDeclOfClassTemplate) {
   Decl *From, *To;
   std::tie(From, To) = getImportedDecl(
       R"(
@@ -1378,7 +1394,7 @@ TEST_P(ASTImporterTestBase, ShouldImportImplicitCXXRecordDecl) {
 
 TEST_P(
     ASTImporterTestBase,
-    DISABLED_ShouldImportImplicitCXXRecordDeclOfClassTemplateSpecializationDecl) {
+    ShouldImportImplicitCXXRecordDeclOfClassTemplateSpecializationDecl) {
   Decl *From, *To;
   std::tie(From, To) = getImportedDecl(
       R"(