[ASTImporter] Handle redecl chain of FunctionTemplateDecls

Summary:
Redecl chains of function templates are not handled well currently. We
want to handle them similarly to functions, i.e. try to keep the
structure of the original AST as much as possible. The aim is to not
squash a prototype with a definition, rather we create both and put them
in a redecl chain.

Reviewers: a_sidorin, shafik, a.sidorin

Subscribers: rnkovacs, dkrupp, Szelethus, gamesh411, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D58494

llvm-svn: 355593

1 files changed, 14 insertions, 34 deletions

diff --git a/clang/unittests/AST/ASTImporterTest.cpp b/clang/unittests/AST/ASTImporterTest.cpp
index 08d57e2e433..00e12d75bc8 100644
--- a/clang/unittests/AST/ASTImporterTest.cpp
+++ b/clang/unittests/AST/ASTImporterTest.cpp
@@ -4197,9 +4197,8 @@ ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(
 ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(
     RedeclChain, Variable, ,
     PrototypeShouldBeImportedAsAPrototypeWhenThereIsNoDefinition)
-// FIXME Enable this test, once we import function templates chains correctly.
 ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(
-    RedeclChain, FunctionTemplate, DISABLED_,
+    RedeclChain, FunctionTemplate, ,
     PrototypeShouldBeImportedAsAPrototypeWhenThereIsNoDefinition)
 ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(
     RedeclChain, ClassTemplate, ,
@@ -4214,9 +4213,8 @@ ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(
     RedeclChain, Class, , DefinitionShouldBeImportedAsADefinition)
 ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(
     RedeclChain, Variable, , DefinitionShouldBeImportedAsADefinition)
-// FIXME Enable this test, once we import function templates chains correctly.
 ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(
-    RedeclChain, FunctionTemplate, DISABLED_,
+    RedeclChain, FunctionTemplate, ,
     DefinitionShouldBeImportedAsADefinition)
 ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(
     RedeclChain, ClassTemplate, , DefinitionShouldBeImportedAsADefinition)
@@ -4230,9 +4228,7 @@ ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(RedeclChain, Class, ,
                                         ImportPrototypeAfterImportedPrototype)
 ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(RedeclChain, Variable, ,
                                         ImportPrototypeAfterImportedPrototype)
-// FIXME Enable this test, once we import function templates chains correctly.
-ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(RedeclChain, FunctionTemplate,
-                                        DISABLED_,
+ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(RedeclChain, FunctionTemplate, ,
                                         ImportPrototypeAfterImportedPrototype)
 ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(RedeclChain, ClassTemplate, ,
                                         ImportPrototypeAfterImportedPrototype)
@@ -4245,9 +4241,7 @@ ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(RedeclChain, Class, ,
                                         ImportDefinitionAfterImportedPrototype)
 ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(RedeclChain, Variable, ,
                                         ImportDefinitionAfterImportedPrototype)
-// FIXME Enable this test, once we import function templates chains correctly.
-ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(RedeclChain, FunctionTemplate,
-                                        DISABLED_,
+ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(RedeclChain, FunctionTemplate, ,
                                         ImportDefinitionAfterImportedPrototype)
 ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(RedeclChain, ClassTemplate, ,
                                         ImportDefinitionAfterImportedPrototype)
@@ -4260,9 +4254,7 @@ ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(RedeclChain, Class, ,
                                         ImportPrototypeAfterImportedDefinition)
 ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(RedeclChain, Variable, ,
                                         ImportPrototypeAfterImportedDefinition)
-// FIXME Enable this test, once we import function templates chains correctly.
-ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(RedeclChain, FunctionTemplate,
-                                        DISABLED_,
+ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(RedeclChain, FunctionTemplate, ,
                                         ImportPrototypeAfterImportedDefinition)
 ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(RedeclChain, ClassTemplate, ,
                                         ImportPrototypeAfterImportedDefinition)
@@ -4274,9 +4266,8 @@ ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(RedeclChain, Function, ,
 ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(RedeclChain, Class, , ImportPrototypes)
 ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(RedeclChain, Variable, ,
                                         ImportPrototypes)
-// FIXME Enable this test, once we import function templates chains correctly.
-ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(RedeclChain, FunctionTemplate,
-                                        DISABLED_, ImportPrototypes)
+ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(RedeclChain, FunctionTemplate, ,
+                                        ImportPrototypes)
 ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(RedeclChain, ClassTemplate, ,
                                         ImportPrototypes)
 // FIXME This does not pass, possible error with Spec import.
@@ -4289,9 +4280,8 @@ ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(RedeclChain, Class, ,
                                         ImportDefinitions)
 ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(RedeclChain, Variable, ,
                                         ImportDefinitions)
-// FIXME Enable this test, once we import function templates chains correctly.
-ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(RedeclChain, FunctionTemplate,
-                                        DISABLED_, ImportDefinitions)
+ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(RedeclChain, FunctionTemplate, ,
+                                        ImportDefinitions)
 ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(RedeclChain, ClassTemplate, ,
                                         ImportDefinitions)
 // FIXME This does not pass, possible error with Spec import.
@@ -4304,9 +4294,7 @@ ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(RedeclChain, Class, ,
                                         ImportDefinitionThenPrototype)
 ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(RedeclChain, Variable, ,
                                         ImportDefinitionThenPrototype)
-// FIXME Enable this test, once we import function templates chains correctly.
-ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(RedeclChain, FunctionTemplate,
-                                        DISABLED_,
+ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(RedeclChain, FunctionTemplate, ,
                                         ImportDefinitionThenPrototype)
 ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(RedeclChain, ClassTemplate, ,
                                         ImportDefinitionThenPrototype)
@@ -4321,9 +4309,7 @@ ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(RedeclChain, Class, ,
                                         ImportPrototypeThenDefinition)
 ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(RedeclChain, Variable, ,
                                         ImportPrototypeThenDefinition)
-// FIXME Enable this test, once we import function templates chains correctly.
-ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(RedeclChain, FunctionTemplate,
-                                        DISABLED_,
+ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(RedeclChain, FunctionTemplate, ,
                                         ImportPrototypeThenDefinition)
 ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(RedeclChain, ClassTemplate, ,
                                         ImportPrototypeThenDefinition)
@@ -4336,9 +4322,7 @@ ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(RedeclChain, Function, ,
                                         WholeRedeclChainIsImportedAtOnce)
 ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(RedeclChain, Variable, ,
                                         WholeRedeclChainIsImportedAtOnce)
-// FIXME Enable this test, once we import function templates chains correctly.
-ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(RedeclChain, FunctionTemplate,
-                                        DISABLED_,
+ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(RedeclChain, FunctionTemplate, ,
                                         WholeRedeclChainIsImportedAtOnce)
 ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(RedeclChain, FunctionTemplateSpec, ,
                                         WholeRedeclChainIsImportedAtOnce)
@@ -4347,9 +4331,7 @@ ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(RedeclChain, Function, ,
                                         ImportPrototypeThenProtoAndDefinition)
 ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(RedeclChain, Variable, ,
                                         ImportPrototypeThenProtoAndDefinition)
-// FIXME Enable this test, once we import function templates chains correctly.
-ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(RedeclChain, FunctionTemplate,
-                                        DISABLED_,
+ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(RedeclChain, FunctionTemplate, ,
                                         ImportPrototypeThenProtoAndDefinition)
 // FIXME This does not pass, possible error with Spec import.
 ASTIMPORTER_INSTANTIATE_TYPED_TEST_CASE(RedeclChain, FunctionTemplateSpec,
@@ -5442,9 +5424,7 @@ TEST_P(ImportFriendFunctionTemplates, LookupShouldFindPreviousFriend) {
       FromTU, functionTemplateDecl(hasName("foo")));
   auto *Imported = Import(FromFoo, Lang_CXX);
 
-  // FIXME Currently chains of FunctionTemplateDecls are not implemented.
-  //EXPECT_EQ(Imported->getPreviousDecl(), Friend);
-  EXPECT_EQ(Imported, Friend);
+  EXPECT_EQ(Imported->getPreviousDecl(), Friend);
 }
 
 INSTANTIATE_TEST_CASE_P(ParameterizedTests, ASTImporterLookupTableTest,